Bad, Bad Headache

[Sethomas]

To be serious, the most common symptom of brain tumors is alteration of the senses, I guess the most common being the pervasive scent of burning rubber. That's fun to tell people because then they start wondering if everything they smell is burning rubber! As for sudden illnesses that might cause a headache, my only guess is meningitis. Very common among college kids. I don't know if it causes headaches, but it makes sense to me that the increased pressure on the skull would cause cranial pain while the brain itself has no sensation.

Edit: If it is meningitis, and look at the symptoms on its wikipedia article if you don't know, then you really need to get it taken care of. You could end up as brain damaged as most of the posters on this board!