I Recently went to the doctor about a suspected UTI. It was incredibly painful to urinate and kinda came out of nowhere. Tested Negative for UTI and Gonorrhea as well as Chlamydia. I was put on antibiotics and since then the pain has subsided to almost nothing. However, i recently noticed this white sore around the opening of my urethra. It is not necessarily painful but I'm concerned. Anybody have any idea of what it might be?