Is it possible to tell the browser that he should not remember the action scripts page?
So when you delete a headline for example. The get action will be ?d=ID where ID is the id of the headline. After removing the headline go to the page without the get variable in the url (the header part).
<?php
if(isset($_GET['d']) && preg_match('{^[0-9]{1,3}$}',$_GET['d'])){
$hid = $_GET['d'];
$deletesql = "DELETE FROM headlines WHERE hid = $hid";
mysql_query($deletesql);
header('Location: panel.php');} ?>
But now you browser history shows the link panel.php?d=23
Can prevent the browser from remembering the page? Maybe a 303 header?
Make the ID hidden in the form and then get it in the form action part using $_POST and then do the delete action and redirect once delete is successful to avoid user from re posting the form.