Upload Process Redirect Not Working

my redirect isn’t working and a blank page is appearing, I’m running error reporting and nothing is happening anyone have any ideas?

<?php
include_once("conninfo2.php");
error_reporting(E_ALL);

$usid = 1;

if(isset($_FILES['files'])){
    $query = "INSERT into files(`filename`,`fsize`,`ftype`,`uploadtimest`, `usid`)
             VALUES(:filename,:fsize,:ftype,now(), :usid)";
    $stmt  = $db->prepare($query);
    $errors= array();
    foreach($_FILES['files']['tmp_name'] as $key => $error ){
        if ($error != UPLOAD_ERR_OK) {
            $errors[] = $_FILES['files']['name'][$key] . ' was not uploaded.';
            continue;
        }
        $filename = $key.$_FILES['files']['name'][$key];
        $fsize = $_FILES['files']['size'][$key];
        $file_tmp  = $_FILES['files']['tmp_name'][$key];
        $ftype = $_FILES['files']['type'][$key];

        if($fsize > 5120){
            $errors[] = 'File size must be less than 5 GB';
            continue;
        }
        try{
            $stmt->bindParam(':filename', $filename , PDO::PARAM_STR );
            $stmt->bindParam(':fsize', $fsize, PDO::PARAM_STR );
            $stmt->bindParam(':ftype', $ftype, PDO::PARAM_STR );
            $stmt->bindParam( ":usid", $_POST['usid']);
            $stmt->execute();

            $desired_dir="fileupload/";

            header('Location: index.php');

            if(is_dir($desired_dir)==false){
                mkdir($desired_dir, 0700);// Create directory if it does not exist
            }
            if(is_file($desired_dir.'/'.$filename)==false){
                move_uploaded_file($file_tmp,$desired_dir.'/'.$filename);
            }else{    //rename the file if another one exist
                $new_file=$desired_dir.'/'.$filename.time();
                move_uploaded_file($file_tmp,$new_file) ;
            }
        }catch(PDOException $e){
            $errors[] = $filename . 'not saved in db.';
            echo $e->getMessage();
		exit();
        }
    }
    if(empty($error)){

    }
}
?>

How far through the code does it get if you add some tracing echo() statements?