With the lock in your hand, put the key in and turn it a few times then take it back out again. Is the cam pointing at 11 or 1 o'clock? If so, the cam has slipped into the wrong alignment. Probably happened when you used the wrong key, if you gave it a good wiggle then that's most likely what caused it. When this happens with thumbturns it tends to fix itself, but not always. Depends on which cam they use, I think.
Anyway, if you want to fix it yourself you're gonna have to pick it, so if you're not good at picking I'd either take it to a locksmith or just buy a new lock. Can get thumbturns pretty cheap on ebay.
If you're a competent picker and know what you're doing when it comes to grabbing the cam, you can try and fix it if you want. When this happens with a normal double sided cylinder you put a key in one side and pick the other, then fusker about with it till you get the alignment back to normal. It's the same idea with thumbturns but you should make a note of the position of the thumbturn in relation to the alignment of the cam so you don't get confused. Stick a bit of tape on one side so you know which side is which, nothing worse than resetting the plug only to realise you haven't actually fixed it
I'd only do this as a temporary fix though, cos it'll probably slip again sooner or later. By now you're probably thinking "screw this" anyway, in which case I'd say buy a new lock and preserve your sanity