来自MySQL数据库的PHP POST循环

我是php的新手，我正在尝试建立一个php测验，该测验从mysql数据库中读取问题和答案。到目前为止，我有以下代码：

require_once("scripts/connect_db.php");
session_start();
$_SESSION['Qid'] = 1;
if (!isset($_POST['answer'])){
    $Qid = $_SESSION['Qid'];
    echo $Qid;
    $stmt = $dbh->prepare("Select * FROM qtable WHERE id = ?");
    $stmt->bindParam(1, $Qid);
    $stmt->execute();
    $result = $stmt->fetchObject(); 
    echo $result->Q . "<br />";
    $stmt = $dbh->prepare("SELECT * FROM atable WHERE Qid = ? ORDER BY rand()");
    $stmt->bindParam(1, $Qid);
    $stmt->execute();
    $result = $stmt->fetchAll();
    echo "<form action=\"test1.php\" method=\"post\">";
    foreach ( $result as $row ) {
        if ( $row['correct'] == 1 ){
            echo "<input type=\"radio\" name=\"answer\" value=\"1\">" .$row['answer']."<br />";
        } else {
            echo "<input type=\"radio\" name=\"answer\" value=\"0\">" .$row['answer']."<br />";
        }
    }   
    echo "<input type=\"submit\" value=\"next\">";
    echo "</form>";     
}
else
{ 
    $Qid = $_SESSION['Qid'] + 1;
    echo $Qid;
    $stmt = $dbh->prepare("Select * FROM qtable WHERE id = ?");
    $stmt->bindParam(1, $Qid);
    $stmt->execute();
    $result = $stmt->fetchObject(); 
    echo $result->Q . "<br />";
    $stmt = $dbh->prepare("SELECT * FROM atable WHERE Qid = ? ORDER BY rand()");
    $stmt->bindParam(1, $Qid);
    $stmt->execute();
    $result = $stmt->fetchAll();
    echo "<form action=\"test1.php\" method=\"post\">";
    foreach ( $result as $row ) {
        if ( $row['correct'] == 1 ){
            echo "<input type=\"radio\" name=\"answer\" value=\"1\">" .$row['answer']."<br />";
        } else {
            echo "<input type=\"radio\" name=\"answer\" value=\"0\">" .$row['answer']."<br />";
        }
    }   
    echo "<input type=\"submit\" value=\"next\">";
    echo "</form>";
}

我的想法是每按一次提交将$ _SESSION ['Qid']递增1，这样我就可以遍历数据库，但到目前为止，我只能上到第二行。任何人都可以在没有Jquery或AJAX的情况下帮助或指导我正确的方法。谢谢