Suggest Treatment For Rashes And Small Cut On Penis Head

I developed a small cut or friction burn on the inside of the opening of the head of my penis after sex with my girlfriend. I am uncircumcised and it is not the frenulum that is cut but a split/burn in the inside of the head. I originally only noticed discomfort during urinating and not the contusion and suspected a uti and took an azo treatment. After closer inspection I noticed the affected area. I also developed a small rash last night which has begun to subside today, and I am not sure what this is from, the azo treatment or something else. From what little I have read on the internet it may have been caused by friction, male yeast infection or balanitis. Std s are not a real possibility due to previous checks for both me and her and a monogamous sexual relationship. My question is, do I need to see a physician? And if not what treatment should I pursue?