toshiba laptop shutting down for no reason, overheating?

[junglewarfare]

My 1 year old toshiba qosmio laptop (which has been great up until today) is randomly shutting down. I will be running something processor intensive like importing to PT, running a game and *click* it turns off. It generally does this when the program i am running is fairly demanding, so I guess this is some kind of overheating problem. The bizarre thing is, these are all things that have NEVER happened until today. For the first 9 months of my laptops life it never ever did this, and it isn't like what I am doing today is more demanding. Sometimes I literally can't load up windows without it powering down. I have put my bedroom fan next to the fan (the part of the laptop which gets hottest and has holes to blow heat out) and that makes it usable. Obviously this is not a real solution, so wtf has happened? I am feeling the comp and it is not like it is especially hot. It seems like the processor or whatever has changed the level at which it powers itself off, it is really weird.

please help me.