i have a hard lump with a sore on it in the groin area in the inguinal section the sore seems to close up and open a little. The lump is about the size of a walnut, or rubber ball. Some research shows that it could be an abscess, but i dont remember getting cut or anything and it just appeared. it hurt for a little while. and there is some pus, it looked like it was going away and the sore was painful for a few days. any help would be appreciated.