Well the good news is I got the coupon code to post to the orders table by carrying the PromoCode session forward into the confirm.php. Do you think that that is ok? It works.
Now, In confirm.php, how would I now make a 0 post into the daily_candy database where that couponCode was? and in the cart.php have that column checked for the 0 and if it is present in the couponCode column have an echo of "Sorry that code was redeemed"