i am a 46 year old woman, with a history of first tubal pregnancy and kock s treatment thereafter for 9 months. Subsequently I had 2 children - a girl 17 years back and a boy 13 years back, both by c-section. 2-3 months back, I noticed a pimple like eruption in my left armpit, but it didn t have any pus or head . But it stayed and didn t go away. It was painless, but sometimes very soft to touch and sometimes hard. Now over last 2 days, it appears to have grown bigger and harder with a small hard lump under the skin , but still painless. What could it be?