points 1 and 3 are a result of point 2. the cart gets cleared when you get to the success page. the order id also gets reset so the next order will create a new record.
most likely there is a php error occurring that is preventing the redirect to the success page.
add the following code at line one of the confirm page to turn error reporting on:
<?php
error_reporting(E_ALL);
ini_set('display_errors','on');
?>