hi, i have a hard lump just below my hip bone. i am a male, 44 yr old. i get bumps from time to time, but haven't one in about 5 yrs. tis one seems slightly tho, as it has to head... but when i squeeze it, a little bit of white pus comes out. also about an inch right around the 'head' there is a hard lump underneath the skin. i suppose it is where the pus has gathered. can you tell me what this might be?