Hi,
Earlier today I noticed a small lump just beside my left nipple. I know it was not there yesterday, or even early this morning. It seems like it just appeared within the last few hours. It's a solid but semi soft mass, as in I can feel a knot, or lump, under the skin, half inside my nipple and half out. Also, it is causing some swelling. It hurts to touch it and it sort of aches when I'm not touching it. I do not see any bite marks etc. to explain it as a bite or sting, however the site is a little red. I am 20 years old and athletic, not overweight.
I do not think it's anything serious, but I am somewhat concerned because of how suddenly it showed up and the fact that it's painful, with no obvious bites or stings. It just appeared. Any input would be appreciated.