I recently had a hard, painful bump on my leg (I'm sure you wanted to know that), and being the internet junky that I am, I looked up a few things on wikipedia, including "boil," since I'd never really known what boils were. I found this sentence:
Boils are most often found on the back, stomach, underarms, shoulders, face, lip, eyes, nose, thighs and buttocks, but may be found elsewhere.Oh, is that all? Is there anywhere they can't be found?
Whatever it was only lasted a few days, so don't worry.