About two weeks after a sexual encounter which included unprotected anal, I started to experience a warmth and tingling sensation in my public region. This led me to get tested for STI and all came back negative. The area was slightly itchy, scrotum, penis and surrounding so I was provided a fungal cream. About a week later my left testicle began to hurt and hang a little lower. The scrotum also became bright red. I went back to the doctor for a uti test and was provided cephalexin. Test was negative and treatment did not work. Went back to the doctor, took a test for gon and chlamydia both negative again but was provided doxicyclin which again did not do much. Testicular pain is now fading but the rash appears to be growing. I have some redness on my penis and scrotum still as well as the area around the base of penis. I have no difficulty urinating and no lesions or sores. Doctors seem to be stumped so was hoping for any insight! I have had pretty severe anxiety regarding this.