I had a small penis lump on the skin of my penis, and after awhile of poking, it became pimple like with white tip. I did not burst it and it dissapeared after awhile, like a normal pimple. Did not leave any scarring. What are the chances of Herpes? On another case, I had a burning sensation on the tip of my penis and tip was slightly red. Went to a doctor and got anti biotics and some medicines for UTI. After a few days, I am back to normal. I never had unprotected sex but might be in contact with fluids. What are the chances of me getting STI in these 2 scenarios? They happened at different times, probably a gap of 3-6 months. What tests should I do to be sure?