Laptop won't display after 9 hour gaming spree

[Angelms]

So I left my laptop on for about 9 hours leaving it on the TF2 title screen because I fell asleep at my desk so when I woke up the screen was frozen and I had to turn the computer off for it to do anything and now I'm getting a blank screen. Everything is on and working but the screen won't work, should this be a GPU or LCD display problem? (I also had my 55' TV used as a second monitor)