Have you done any editing on the confirm.php page? It seems that the normal redirect that would occur is just not happening. In your globals file do you have test mode enabled? If so it may be responsible for this.
Please post back and describe what settings you have in your globals file without divulging any sensitive details. Along with this info post back with a copy of your confirm page and I can help you determine what is going wrong by adding in some debug code to this page.