Blood blister on back of cartilage piercing!!!?

a couple weeks ago i got a huge gross red blood blister on the back of my cartilage ear piercing!! it poped on its own and there was just a small bump left over except it wasnt a blood blister. now i just got a new blood blister and i dont know what to do because its going to pop on its own and there just going to keep coming back since this is the 2nd time of me getting it. i also got the piercing over 6 months ago and i didnt take the earring out when i got the blood blister because i didnt want it to close up and didnt think i had to. please help!