what about staph infection? are they really painful....explosive like a zit?  see your doctor for confirmation and to make sure it is not MRSA.  you can pick it up from a dirty towel, or have it develop in conjunction with an in-grown hair.  staph is a common organism that often occurs in the nose and behaves itself unless there is an opportunity to enter another part of the body and cause disease. i am sure i had a brief encounter with a couple of pustules on my chest a few years back when my son was blowing his nose in my shower towel.  needless to say we had a quick education in personal hygiene and the problem was solved. hope this is helpful. good luck!