M Effect 2 Disk unreadable?

Well I got m effect 2 for Christmas of 2010 and played it 5 times in the last month (January) and just today I accidentally hit my xbox while the game was going and now its unreadable right near the beginning right after you talk to the illusive man and head to the door to get to the shuttle to freedoms progress right when the loading screen should begin but its just black and then pops up disc unreadable. There is one tiny scratch about a centimeter away from the edge of the disc don't know if that's what causing it to become unreadable. There are no burn marks at all. Also, at the center of the disc where the holographic xbox 360 logo is its a little burned but the game was able to boot up can the laser really burn that sticker? and is that burnt sticker the problem for the game saying disc unreadable on that specific part? And is that sticker the data ring? I really don't know what went wrong I tried cleaning it with toothpaste which was the wrong idea and now it wont even boot up keeps saying disc unreadable should I just get a new copy or get the disc buffed? :(