I am a male and 23, I think i'm fairly healthy, not sexually active, and don't smoke and rarely drink alcohol.
I was taking Bactrim since one of my doctors thought I had an acute prostate infection, over time I became unable to sit down due to the pain, ,my penis feels slightly bruised, extreme pain in my testicles if they're in some positions but not others, sometimes the perineum twitches or spasms at times but hurts a lot when sitting down, starting to urinate usually is a little more difficult and painful sometimes causing me to stop urinating and start back up. When i sit down it feels like there's a golf ball where my perineum is. Along with these problems I noticed some weird looking veins on my penis, not sure if they're veins or something else, when I was erect and applied a little bit of pressure to that area it started to hurt, and made some other areas of the penis hurt too, and after an hour or two made my penis feel a bit bruised even in areas I didn't touch. Not sure if it's a vein and I shouldn't bother it or if it's a different issue entirely. Before such major issues started i was getting strings on pain from i think under my scrotum to my penis when masturbating, now the pain overall is so bad even when i'm not masturbating that i'm too afraid to try. Finally i'm having small red dots over my body when i woke up this morning and they itch, I've been off Bactrim for about 2 or 3 days.
At first before i went to the doctor i was having a weird buzzing/vibration in my penis with a bit of pain while masturbating, it felt like a string from under my testicles, possibly the pelvic floor muscle into my penis, also when i would ejaculate it sometimes felt block like it couldn't come out, but eventually the orgasm was much stronger, but in a less enjoyable way.