Fejlen i login script?

Denne kode giver en blank side... Kan simpelt hen ikke se fejlen.

<?php
session_start();
require_once ('./includes/mysql_connect.php');

if(isset($_POST["email"], $_POST["pwd"])) {
    $dotjek = mysql_query("(SELECT fnavn AS n, email, pwd, status FROM studerende WHERE email ='". $_POST["email"] ."' AND activated IS NULL) UNION (SELECT ins_navn AS n, email, pwd, status FROM institutioner WHERE email ='". $_POST["email"] ."'AND activated IS NULL)") or die (mysql_error());
    $brugertjek = mysql_fetch_object($dotjek);
    if($brugertjek->email != $_POST["email"]) {
        $_SESSION["navne_fejl"] = 1;
        header("Location:logind.php");
        exit;
    }
    $_SESSION["email"] = $_POST["email"];

    if($brugertjek->pwd != md5($_POST["pwd"])) {
        $_SESSION["password_fejl"] = 1;
          header("Location:logind.php");
          exit;
    }
    else {
        $stat = $brugertjek->status;
        $_SESSION["status"] = $stat;
        if ($stat == 1) {
            $_SESSION["navn"] = $brugertjek->n];
        }
        if ($stat == 2) {
            $_SESSION["navn"] = $brugertjek->n;
        }
        if ($stat == 3) {
            $_SESSION["navn"] = "Admin";
        }
        else {
            $_SESSION["navn"] = "Gæst";
        }
   
        header("Location:index.php");
        exit;
    }

mysql_free_result($dotjek);

}
header("Location:index.php");
?>