in late october, i discovered a very painful bump in my right leg. the doctor diagnosed it as a cyst. i was prescribed an antibiotic. the antibiotic made the pain go away and the swelling went down quite a bit, but i could still feel the cyst. the doctor said that it was not necessary to drain it. yesterday, i found another cyst on the same leg. it is so painful that i can barely walk. what could be causing this?