Clear session after form has been submitted

I have built a series of forms (Parent > child > child > etc) as an e-commerce checkout. On the final step, payment is processed, and a number of Record Rules run that insert connected records. Occasionally, a user clicks the BACK button on their browser (I'm guessing this is what they do) and then RE-submits the form. Amongst other problems, it creates a duplicate payment record (and actually processes the card again).

Has anyone figured out a way to clear a form session (or something to this affect), after a form has been submitted, such that if a user clicks BACK on the browser, they won't be able to resubmit the form with the previously filled in session information?