Help with the Sims 3!?

Okay so, this is going to sound bad. I was all hyped about the Sims 3 and when i heard news of the torrent that was out, I tried to download the torrent. I couldnt get the torrent to work so I just gave up because I was planning ou=n buying the game anyway. I got the game on June 2nd but now my launcher keeps telling me that I'm running an unauthorized version of the sims 3.. but Im playing the legal copy that I got. I tried to register my game online but it says that my serial code is already being used.. any ideas how I can fix this problem?