I had shoulder surgery Friday June 8, and I tried to shave my arm pit prior to post op visit 1 week later. A day later I noticed a small knot under my arm, itching and painful. Then two more lumps, red and swollen. My arm was in a sling and the first week I wore sleeveless and shoulderless shirts to make dressing easier, but arm pit moister did seem to be a problem. I tried very hard to keep the area clean. I had used deoderant after shaving, but it was a natural crystal water based kind. I have since stopped trying to use anything but just keeping it clean. Should I be concerned? I just want them to go away because they are painful and uncomfortable.