Macbook Pro freezes on startup screen

I was playing Modern Warfare online, when a new map was about to load. The game was a but laggy since I was running ScreenFlow to record it, but nothing big. While loading the next map, the Computer suddenly froze. I couldn't quit, force quit, do anything, so I did a force shut down of my comp. Now I can't get past the startup screen (the gray one with the apple and little spinning wheel) and I have tried a lot of stuff, like using Single User mode to modify harddrive to fix it, but that doesn't work. Can anyone help me, because I'm pretty screwed.

P.S. I don't have any install disks so please don't suggest I do that

Without a bootable disk to work with, I think you're right, you're screwed.

It sounds to me as if your HD failed. You need to take it in for service.