Shady business at ATT

I have recently switched phones from the iphone 3G to the HTC Incredible. So no more ATT and with Verizon. Reason I switched is because Apple has ATT by the balls. ATT has one crappy android phone and more crappy ones are coming. I bought a 3G iphone last which I paid full price for. As it turns out they extened my contract without me knowing and the ATT reps I spoke to on the phone could not even find the price I paid for the phone? So I believe that some shady shit happened that day. I believe they rung me up as an early upgrade which extends my contract and supposed to be charged $200 but charged me full price and pocketed the other $300! The first rep I spoke to said no matter what buying and iphone signs you up for a new contract incorrect or lie take your pick. The rep I spoke to another time as well as the guy that I spoke to today said my contract should not have been extended if I paid full price. Now I can get out of the ETF if I can show the reciept which I can not find! Anyway does this situation sound shady to anyone else?