Yesterday I spent almost all day reading stuff on my computer.
:-?

Uh-oh, sounds like compy addiction to me... just teasing, you already said it's probably not from the computer.
Do you have a regular sleeping pattern, Raspberry? I don't remember, but you said that school is out for you? (or close to?) Since there is such a thing as too much sleeping, I suggest you go outside for a bit for fresh air, even if it's just sitting under a porch or whatnot. Just try getting around a bit, or take a good look at the environment that you're computer is in. Have good lighting? Have you been snacking a lot? Has your eating habits changed? Just try to observant of anything that has changed.
And I've gone off on a tangent, hoping the problem is not as serious as I made it to be. Feel better soon, okay? *hugs*
-- Oh yes. The anger management. Solved.