What Causes Red Bump On Penis Inspite Of Being Tested Positive For Mouth Herpes?

Hello, I recently have been experiencing really estrange symptoms, I m a gay male, sexually active, 23 years old, less than a month ago I got tested for HVI, chlamydia and gonorrhea they were all negative. I had a sexual experience after this, it was a one time thing and left me feeling pretty concern because im not used to having one night stands. started a small red spot on my penis, now its a bit bigger and I have this pinch like feeling at times (on and off), well.. because I was so worry I decided to go get a blood test for Herpes and syphilis and I resulted negative for syphilis and negative for genital herpes but positive for mouth herpes. I m so confused, I don t know whats causing my symptoms in my genital area, could it be pure anxiety? this is depressing me and I don t know how to seek for help. should I visit a urologist?