pagination does not load the next records

Hello, after running a search, it delivers the amount specified in the code, so far so good ... now enter my problem, I'm using url friendly and even if the form send with "...? page = 1" I think it does not assign value to $ string,
errors submitted:

pagination link ("...? page = 2" and so on) does not load the page or the next records; if you change pages and press on the browser back, do not load the page (neither with or without the search items) after running the search the items remain even if I go to another page and go back (by clicking on the directional page where they list the records) it displays the search items + items that are listed by default on the page

Form Code: (pg = site link)

<form class="form-inline" name="search" id="search_form" method="post" action="<?php echo pg.'/videos?pagina=1'; ?>">
    <div class="input-group">
        <input type="text" class="form-control" placeholder="Search" name="pesquisar" id="pesquisar" value="">
        <span class="input-group-btn">
            <button type="submit" class="btn btn-primary"><i class="fa fa-search" aria-hidden="true"></i></button>
        </span>
    </div>
</form>

Index:

<!-- Conteudo -->
<?php 
$url = (isset($_GET['url'])) ? $_GET['url']:'';
$explode = explode('/',$url);


$paginas = array('home','categories','videos','video');
if(isset($explode[0])&& $explode[0] == ''){
    include "home.php";
}elseif($explode[0] != ''){
    if(isset($explode[0]) && in_array($explode[0], $paginas)){
        include $explode[0].".php";
    }else{
        include "home.php";
    }
}
?>

Page that receives the records:

<?php 
    $url = (isset($_GET['url'])) ? $_GET['url']:'';
    $explode = explode('/',$url);
    $categoria = $explode[1];

    $query_vid = "SELECT * FROM videos ORDER BY id DESC";
    $resultado = mysqli_query($conectar, $query_vid);


    $query = "SELECT * FROM videos WHERE categoria_id='$categoria' or categoria_id2='$categoria' or categoria_id3='$categoria' or categoria_id4='$categoria' or categoria_id5='$categoria' ORDER BY id DESC";
    $resultado_vid = mysqli_query($conectar, $query);
?>
<?php
        if($_SERVER['REQUEST_METHOD']=='POST'){
            $pesquisar = $_POST['pesquisar'];
            $pagina = 1;
            $_SESSION['pesquisar'] = $pesquisar;

            listar($pesquisar, $pagina, $conectar);

        }elseif((isset($_SESSION['pesquisar']))){
            $pagina = (isset($_GET['pagina'])) ? $_GET['pagina'] : 1;
            listar($_SESSION['pesquisar'], $pagina, $conectar);
        }
        function listar($pesquisar, $pagina, $conectar){
            //Selcionar todos os registros da tabela

    $query_pesqu = "SELECT * FROM videos WHERE nome LIKE '%$pesquisar%' or desc_vid LIKE '%$pesquisar%' or tags LIKE '%$pesquisar%' ORDER BY id DESC";
    $resultado_pesqu = mysqli_query($conectar, $query_pesqu);

    //Contar o total de registros
    $total_pesq = mysqli_num_rows($resultado_pesqu);

    //Setar quantidade de registros por pagina
    $qnt_result_pg = 3;

    //Calcular o inicio da visualização
    $inicio = ($qnt_result_pg*$pagina)-$qnt_result_pg;

    //Selecionar os registros a serem apresentado na página
    $query_pesq = "SELECT * FROM videos WHERE nome LIKE '%$pesquisar%' or desc_vid LIKE '%$pesquisar%' or tags LIKE '%$pesquisar%' ORDER BY id DESC LIMIT $inicio, $qnt_result_pg";             
    $resultado_pesq = mysqli_query($conectar, $query_pesq);
?>
<?php if ($pesquisar != ''){?>

while ($linhas_pesq = mysqli_fetch_assoc($resultado_pesq)){
$imagem = pg.'/media/videos/'.$linhas_pesq['imagem'];
$vid_nome = $linhas_pesq['nome'];
$vid_nome = str_replace(" ","-",$vid_nome);
$link_vid = pg.'/video/'.$linhas_pesq['id'].'/'.$vid_nome;      
?>
<div id="<?php echo $linhas_pesq['id'] ?>" class="col-sm-4 m-b-15" title="<?php echo $linhas_pesq['nome'] ?>">
<div class="well well-sm">
<div class="thumb-overlay">
<a href="<?php echo $link_vid; ?>">
<div class="thumb-overlay">
<img src="<?php echo $imagem; ?>" id="<?php echo $linhas_pesq['id'].".jpg" ?>" class="img-responsive ">
    <div class="hd-text-icon">HD</div>                                  
    <div class="duration"><?php echo $linhas_pesq['tempo'] ?></div>                                     
</div></a>
<div class="actions"></div></div>
<a href="<?php echo $link_vid; ?>">
<div class="video-title title-truncate"><?php echo $linhas_pesq['nome'] ?>  </div></a>
<div class="video-views pull-left">viewr</div>
<div class="video-rating pull-right no-rating">
    <i class="fa fa-heart video-rating-heart no-rating active"></i> <b>-</b>
</div><div class="clearfix"></div>                                      
</div></div>
<?php }   
            //************* INICIO PAGINAÇÂO **************/
            //Qunatidade de paginas
            $quantidade_pg = ceil($total_pesq / $qnt_result_pg);

            //Limite de link antes e depois 
            $MaxLinks = 2;

            echo "<br>";

            echo "<a href='videos?pagina=1'>Primeira</a> ";

            for($iPag = $pagina - $MaxLinks; $iPag <= $pagina - 1; $iPag++){
                if($iPag >= 1){
                    echo "<a href='videos?pagina=$iPag'>$iPag</a> ";
                }
            }

            echo " $pagina ";

            for($dPag = $pagina + 1; $dPag <= $pagina + $MaxLinks; $dPag++){
                if($dPag <= $quantidade_pg){
                    echo "<a href='videos?pagina=$dPag'>$dPag</a> ";
                }
            }

            echo "<a href='videos?pagina=$quantidade_pg'>Última</a>";
        }}
    ?>          

<?php if ($pesquisar == ''){?>
<?php if ($categoria == ''){
while($linhas = mysqli_fetch_assoc($resultado)){ 
$imagem = pg.'/media/videos/'.$linhas['imagem'];
$vid_nome = $linhas['nome'];
$vid_nome = str_replace(" ","-",$vid_nome);
$link_vid = pg.'/video/'.$linhas['id'].'/'.$vid_nome;

?>

<div id="<?php echo $linhas['id'] ?>" class="col-sm-4 m-b-15" title="<?php echo $linhas['nome'] ?>">
<div class="well well-sm">
<div class="thumb-overlay">
<a href="<?php echo $link_vid; ?>">
<div class="thumb-overlay">
<img src="<?php echo $imagem; ?>" id="<?php echo $linhas['id'].".jpg" ?>" class="img-responsive ">
    <div class="hd-text-icon">HD</div>                                  
    <div class="duration"><?php echo $linhas['tempo'] ?></div>                                      
</div></a>
<div class="actions"></div></div>
<a href="<?php echo $link_vid; ?>">
<div class="video-title title-truncate"><?php echo $linhas['nome'] ?></div> </a>
<div class="video-views pull-left">viewr</div>
<div class="video-rating pull-right no-rating">
    <i class="fa fa-heart video-rating-heart no-rating active"></i> <b>-</b>
</div><div class="clearfix"></div>                                      
</div></div>
<?php }} ?>

<?php 
if ($categoria != ''){
while($linhas_vid = mysqli_fetch_assoc($resultado_vid)){
$imagem = pg.'/media/videos/'.$linhas_vid['imagem'];
$vid_nome = $linhas_vid['nome'];
$vid_nome = str_replace(" ","-",$vid_nome);
$link_vid = pg.'/video/'.$linhas_vid['id'].'/'.$vid_nome;   
?>

<div id="<?php echo $linhas_vid['id'] ?>" class="col-sm-4 m-b-15" title="<?php echo $linhas_vid['nome'] ?>">
<div class="well well-sm">
<div class="thumb-overlay">
<a href="<?php echo $link_vid; ?>">
<div class="thumb-overlay">
<img src="<?php echo $imagem; ?>" id="<?php echo $linhas_vid['id'].".jpg" ?>" class="img-responsive ">
    <div class="hd-text-icon">HD</div>                                  
    <div class="duration"><?php echo $linhas_vid['tempo'] ?></div>                                      
</div></a>
<div class="actions"></div></div>
<a href="<?php echo $link_vid; ?>">
<div class="video-title title-truncate"><?php echo $linhas_vid['nome'] ?>   </div></a>
<div class="video-views pull-left">viewr</div>
<div class="video-rating pull-right no-rating">
    <i class="fa fa-heart video-rating-heart no-rating active"></i> <b>-</b>
</div><div class="clearfix"></div>                                      
</div></div>

<?php }} ?>                         
<?php } ?>