Someone please help and give some advice.

So after experiencing burning in my penis 1 day after I lost my virginity to a girl the pain and burning spread to my testicles and sides and lower back after a few weeks. I got urine std tests done after about a month and they came back clean and I also went on 1 week of doxy right after getting those tests. But the doxy did nothing and I tried to forget about it. I've been seeing a urologist for about 2 months now and he gave me a digital rectal exam and it hurt a lot and he prescribed me 10 days worth of septra. After the 10 days were up the pain in my lower back went away completely and the pain in my sides almost all went away. I had another appt with him about 3 weeks later and he said I could try cipro or more septra so I went on 2 more weeks of septra and it did nothing. I also had a semen culture and had an appt today and it came back clean. I also did a prostate massage today to analyze my prostate fluid and he prescribed me 28 days of norflax, idk what my next steps should be. I have another appt in 28 days but will probably try and move it up based on if I feel any better or not. What are my next steps and what should I do? I'm so fucking scared and don't know what to do anymore. Someone please offer some advice.