Hello,
Hard rubber like ball under the skin of the shaft of the penis is commonly a
lymphocele which can be seen after sex or
masturbation. It is a harmless condition and should go away on its own. However, it can be genital warts if it does not go away or gets reduced in size. It may cause discomfort or itching.
Warts are STI caused by
HPV. You are suggested to get clinically examined by a
Urologist, get it removed at the earliest. Get
STD tests done. Treatment includes topical creams or surgical removal. The warts may reappear after removal, as there is no cure for the HPV virus.
However, you will be treated for other STI with antibiotics and antivirals if detected positive. Avoid sex for a couple of days. Take care of your hygiene. Get treated at the earliest.
Take care. Hope I have answered your question. Let me know if I can assist you further.
Regards,
Dr. Nupur K., General & Family Physician