I was wondering what are signs of brain swelling?

Depress CNS function: In general swelling of the brain leads to depression of central nervous system function. This leads to drowsiness, dizziness, confusion, and headaches. With more severe swelling there can become focal neurologic symptoms depending on the type of herniation that occurs. I hope this helps.

Encephalitis: Brain swelling, aka "encephalitis" will cause most people to complain of headaches, trouble with speech/language, perception of phantom smells, very irritable, changes of personaility, lowered state of alertness, lethargy, become hypoactive, fever, flu like symptoms, muscle aches, seizures, double vision, nausea/vomiting, stupor, obtundation, coma.