I have had a bump behind my ear for 4 years and it's starting to get worse, what could it be? (photo)

I noticed about 4 years ago a bump on the back of my conchal bowl that had never been there before. I thought it may have been a pimple and tried to squeeze it but it just hurt. Not too long after I tried squeezing it again and white stuff/clear liquid came out and then started bleeding and the bump was gone. A few days later it was back and has never left. Now if I squeeze it just blood will come out and it will hurt for a few seconds. All around it the skin behind my hear is dry and peeling.