Hello. I recently broke up with a long term 5 year girlfriend. About three months later, in a night of careless thinking, I had unprotected sex with an old high school ex. As this was going on I was just beginning talking to a new girl (maybe a few weeks into flirty conversation that probably stepped past the boundary of just friends). It now appears that there could be a potential that a relationship could happen between us. The problem... a few days after my episode with my ex I started having pretty severe genital pain. I have never had any bumps, sores, or discharge. The pain was mainly on surface of the tip (although I have felt discomfort in my urethra as well) and a reddish rash would sometimes appear after the shower, but would fade away soon afterwards. Also note, there was pretty intense pain after masturbation, but it didn't seem to occur until the days that followed (I regretted that action for weeks). I have taken two separate HIV, chlamydia, and gonorrhea tests through urine, blood, and throat swab samples and everything came up negative. My ex also has said that she is STI free from her last exam, although she admitted to having a one night stand with a guys since then. The doctor initially thought it might have been a non-STI bacterial infection of my right epididymis and gave me a strong 14 day cycle of antibiotics. This however didn't fix any of the pain I was feeling, which was keeping me up at night. This torment continued for almost 7-8 weeks before I was referred to a urologist and dermatologist. They both ruled out herpes (which I was fearing) due to the length of the outbreak and the lack of herpes sores. However, I have never officially been tested since I was recommended not to take them because they are only accurate if they can swab from a sore. The urologist didn't know what it was and the dermatologist said it might be contact dermatitis from soaps or other irritants I was exposed to from that night. I have since used a hydrocortisone cream that helped almost immediately. It has now been 3 days since I've started this cream and I feel close to normal again.
Question 1) Is this likely the diagnosis? Can I be sure that I'm still STI free?
This relates directly to question 2) Because I'm (hopefully) beginning a new relationship, where this incident occurred embarrassingly at its origins when we weren't as close, I would not like this to be brought up in fear that it would jeopardize what we have. Should I tell her about possibly carrying and STI since I was in pain for so long. And if so, how so?
I don't know when our first sexual encounter is going to happen, but I fear it might happen soon and I'm not sure how to address this issue.