Error parsing data org.json.JSONException

I'm new to Android and I also do not really understand JSON so I was doing a login tutorial but it gave me a bug and I do not know what to do. I think it's a php error or database since my class register and my class insert query also give the same error but my class to see the queries works fine. This is the error:

  

Error parsing data org.json.JSONException: Value ï »¿ï» of type   java.lang.String can not be converted to JSONObject

Android Code:

    public class Login extends Activity implements OnClickListener{

        private EditText user, pass;
        private Button mSubmit, mRegister;

        // Progress Dialog
        private ProgressDialog pDialog;

        // JSON parser class
        JSONParser jsonParser = new JSONParser();

        //php login script location:

        //localhost :


//testing on your device
        //put your local ip instead,  on windows, run CMD > ipconfig
        //or in mac's terminal type ifconfig and look for the ip under en0 or en1
       // private static final String LOGIN_URL = "http://xxx.xxx.x.x:1234/webservice/login.php";

        //testing on Emulator:
        private static final String LOGIN_URL = "http://www.cresceranorte.com/WebService/login.php";

      //testing from a real server:
        //private static final String LOGIN_URL = "http://www.yourdomain.com/webservice/login.php";

        //JSON element ids from repsonse of php script:
        private static final String TAG_SUCCESS = "success";
private static final String TAG_MESSAGE = "message";

        @Override
protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.login);

        //setup input fields
        user = (EditText)findViewById(R.id.username);
        pass = (EditText)findViewById(R.id.password);

        //setup buttons
        mSubmit = (Button)findViewById(R.id.login);
    mRegister = (Button)findViewById(R.id.register);

        //register listeners
        mSubmit.setOnClickListener(this);
        mRegister.setOnClickListener(this);

}

    @Override
public void onClick(View v) {
    // TODO Auto-generated method stub
    switch (v.getId()) {
        case R.id.login:
                        new AttemptLogin().execute();
                    break;
            case R.id.register:
                    Intent i = new Intent(this, Register.class);
                        startActivity(i);
                    break;

       default:
                    break;
            }
    }

        class AttemptLogin extends AsyncTask<String, String, String> {

             /**
      * Before starting background thread Show Progress Dialog
      * */
                boolean failure = false;

                @Override
        protected void onPreExecute() {
                super.onPreExecute();
                pDialog = new ProgressDialog(Login.this);
                pDialog.setMessage("Attempting login...");
                pDialog.setIndeterminate(false);
                pDialog.setCancelable(true);
                pDialog.show();
            }

                @Override
        protected String doInBackground(String... args) {
                // TODO Auto-generated method stub
                 // Check for success tag
                int success;
                String username = user.getText().toString();
                String password = pass.getText().toString();
                try {
                    // Building Parameters
                        List<NameValuePair> params = new ArrayList<NameValuePair>();
                        params.add(new BasicNameValuePair("username", username));
                        params.add(new BasicNameValuePair("password", password));

                        Log.d("request!", "starting");
                        // getting product details by making HTTP request
                    JSONObject json = jsonParser.makeHttpRequest(
                                       LOGIN_URL, "POST", params);

                        // check your log for json response
                    Log.d("Login attempt", json.toString());

                        // json success tag
                   success = json.getInt(TAG_SUCCESS);
                 if (success == 1) {
                          Log.d("Login Successful!", json.toString());
                           Intent i = new Intent(Login.this, ReadInfo.class);
                          finish();
                                startActivity(i);
                          return json.getString(TAG_MESSAGE);
                        }else{
                          Log.d("Login Failure!", json.getString(TAG_MESSAGE));
                         return json.getString(TAG_MESSAGE);

                        }
                    } catch (JSONException e) {
                    e.printStackTrace();
                    }

          return null;

      }
   /**
         * After completing background task Dismiss the progress dialog
     * **/
                protected void onPostExecute(String file_url) {
            // dismiss the dialog once product deleted
                pDialog.dismiss();
                if (file_url != null){
                        Toast.makeText(Login.this, file_url, Toast.LENGTH_LONG).show();
                    }

            }

        }

    }

PHP Code:

<?php

//load and connect to MySQL database stuff
require("config.inc.php");

if (!empty($_POST)) {
    //gets user's info based off of a username.
    $query = "
            SELECT
                id,
                username,
                password
            FROM users
            WHERE
            username = :username
        ";

    $query_params = array(
        ':username' => $_POST['username']
    );

    try {
        $stmt   = $db->prepare($query);
        $result = $stmt->execute($query_params);
    }
    catch (PDOException $ex) {
        // For testing, you could use a die and message.
        //die("Failed to run query: " . $ex->getMessage());

        //or just use this use this one to product JSON data:
        $response["success"] = 0;
        $response["message"] = "Database Error1. Please Try Again!";
        die(json_encode($response));

    }

    //This will be the variable to determine whether or not the user's information is correct.
    //we initialize it as false.
    $validated_info = false;

    //fetching all the rows from the query
    $row = $stmt->fetch();
    if ($row) {
        //if we encrypted the password, we would unencrypt it here, but in our case we just
        //compare the two passwords
        if ($_POST['password'] === $row['password']) {
            $login_ok = true;
        }
    }

    // If the user logged in successfully, then we send them to the private members-only page
    // Otherwise, we display a login failed message and show the login form again
    if ($login_ok) {
        $response["success"] = 1;
        $response["message"] = "Login successful!";
        die(json_encode($response));
    } else {
        $response["success"] = 0;
        $response["message"] = "Invalid Credentials!";
        die(json_encode($response));
    }
} 
?>

PHP code config.inc :

<?php

$username = "XXXXX";
$password = "XXXX";
$host = "XXXX";
$dbname ="android";

$options= array(PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8');

try
{
    $db = new PDO("mysql:host={$host};dbname={$dbname};charset=utf8", $username, $password, $options);
}
catch(PDOException $ex)
{
    die("Failed to connect to the database".$ex->getMessage());
}

$db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$db->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE,PDO::FETCH_ASSOC);

if(function_exists('get_magic_quotes_gpc') && get_magic_quotes_gpc())
{
    function undo_magic_quotes_gpc(&$array)
    {
        foreach($array as &$value)
        {
            if(is_array($value))
            {
                undo_magic_quotes_gpc($value);
            }
            else
            {
                $value = stripslashes($value);
            }
        }
    }

    undo_magic_quotes_gpc($_POST);
    undo_magic_quotes_gpc($_GET);
    undo_magic_quotes_gpc($_COOKIE);
}

header('Content-Type: text/html; charset=utf-8');

session_start();

?>