I have something on my groin. every so often it pops out like a mountain of red tissue. then it goes back in. the skin becomes flat and the whole area around it is purple. I went to a dermatologist 2 weeks ago. he took a culture of it and said its nothing/cyst. gave me some pills to make sure it doesn't get infected. while i was on the pills it seemed to have closed up until about 2 days ago. please help.