I think I have a brain tumor ...

[Mechaman]

I know you probably feel like hell or what not but it's probably just an extreme migraine caused by lots of stress or something to that effect.

And it's important not to jump to conclusions when looking up stuff on the internet.  Last year I had a lot of stomach troubles: episodic recurrent diarrhea, constant stomach pain, a pain in my chest that feels like I'm having a heartattack after I eat something.  You name it.
First search result that came up: Intestinal Cancer.

I went to the doctor, took a few tests, or what not and it turned out to be Irritable Bowel Syndrome.  Not a pleasant diagnosis, but it beats worrying about whether or not you will live to see graduation.

Sometimes, non-life threatening health conditions feel like the end of the world.  Tis a bitch, it really is.

I would see a doctor and then go from there.