I know what you mean! About a week after my intial diagnosis, I was at a kids birthday party and one of the adults there was complaining that she had cut her hand on a soup can and was trying to find a lawyer to sue the maker of the soup. Mind you, she didn't even need stitches or anything - "it just hurts and i can't work...". She did pretty well playing air hockey with her son though. Hmmm... Anyway, I was so tempted to just throw in the brain tumor thing to shut her up, but figured she must be so starved for attention, I just let her go on. It got to be pretty funny after a while.
Right after my surgery, whenever anyone would complain about trivial things, I would just say "Ok, anyone here who just had their head cut open with a power saw - raise your hand". They stopped pretty quick when i was the only one raising my hand. I guess you just need to make them put things in perspective every so often.
Hang in there. Remember that some people just feel the need to complain about little things no matter what, and somehow their paper cut seems worse than your brain tumor. Keep your sense of humor - that always helps!
Lori