Actually, I do feel a slight lump (about the size of a nickel) above my right ear and it changes in size, sensitivity, etc. My PCP wrote it off, but sometimes it feels very warm too.
I should mention that I have had some auditory hallucinations within the last few weeks.
FWIW, this entire thread is really something you should bring up with your doctor(s), and not rely on people on the internet for anything more than empathy.
Nobody can diagnose you with a brain tumor over the Internet and primary brain tumors are in fact rare - about 1.3% of all cancers.