Alright, calm down it is okay. Pm an admin or smod and tell them what happened. They can check your logs and see what went on and further investigate. So you don't have to worry at all.
Edit: Look at the bottum of the forums on the main page and pm one of the users who have a Blue or Red name. They are the mods/admins currently online.
judging from the time of your transaction and the time this thread was made, i'd say that you made the thread as soon as you accidentally bought a texture you didnt want