Hi Thank you for asking HCM. I have gone through your query. As you have only one bump it can be most likely folliculitis. This will come in hair follicles. If you send a picture of it then it will be more helpful in identifying. Other possibility is genital herpes. This usually presented as fluid filled rashes and will be assessed with pain or burning sensation and itching. If folliculitis then applying betadine ointment will be helpful. In case there is collection of pus inside and drainage should be done. For that you can approach your GP. Hope this may help you. Let me know if anything not clear. Thanks.