Here's the story.
I was playing mw3 and i went shopping for about 3 hours. When i got back my brother was playing on my xbox and i didnt know until i came back. I saw a USB in the xbox 360 and i asked him what are you doing? He said nothing , so i grabbed the conroller off him and he was on survival mode on mw3. I backed out into the lobby and i thought im not level 50. I asked him how did u rank up so quickly and he said i modded it with the usb. Please help i dont want to be banned and i have lots of things on xbox live. Could somebody like make my profile so its like nothing has been modded? Im really afraid of getting banned and i have cod elite and all the dlc's.