Have you ever been tested for mycoplasma genitalium?
The herpes IgM is a terrible test and shouldn't have been done on you. First, the timing was way off, as it is designed to look for new infections, and you wouldn't have had a new infection if you'd not been sexually active for well over a year. Second, it is just unreliable. It can cross react with other herpes family viruses, like chicken pox. My own IgM was negative when it should have been positive, and positive when it should have been negative. Ignore that you had it. It shouldn't be done on anyone other than newborns.
https://www.kevinmd.com/blog/2013/07/order-herpes-igm-blood-test.html
https://www.statnews.com/2017/01/26/flawed-herpes-testing-leads-to-false-positives/
So what do you have? It honestly could be chronic prostatitis. Classic symptoms of that are penis tip pain and painful erections.
https://www.healthlinkbc.ca/health-topics/hw73293
https://www.webmd.com/men/guide/prostatitis#1
https://www.medicalnewstoday.com/articles/322457.php
It definitely wouldn't hurt to make sure you've been tested for mycoplasma. You definitely want to rule out all possible causes of infection.