I found a lump under my armpit, quite deep, began messing with it and although it was difficult to burst, I pressed and pushed it enough and it burst and thick, green and brown pus came oozing out. It was painful before doing this but more painful after. I waited and thought it would just disappear, but now it has become a bigger, dome shaped/flatter, lump underneath my armpit, not so sensitive to touch. I've waited about 4 days for it to go away but it is still there.