Hello,
This may be a sebaceous cyst. It is a closed sac occurring just under the skin which contains a "pasty" or "cheesy" looking substance called keratin. Blocked sebaceous glands, swollen hair follicles and excessive testosterone production will cause such cysts.
Generally no treatment is required but they become painful then it means they are infected, then surgical excision by traditional wide excision, minimal excision, and punch biopsy excision may be required.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
Leave it alone! You picked on it once and now??? Either go to a dermatology MD or maybe someone at a spa that does Esthetics will extract it in a safe, clean way.