Pain and swollen testicles, pain in urethra, no discharge

[pianoandwine22]

I am experiencing swollen scrotum/testicles in which they seem to swell up and retract. I also have pain that comes and goes in the urethra close to the body (not the head). No pain during urination and no discharge. I got tested for chlamydia, gonorrhea and HIV RNA at day 5 and day 13 after possible exposure and both came back negative. My symptoms started happening 5 days after my last sexual encounter. It has been 3 weeks with this pain now. I sometimes also feel my legs/feet hot and with some pain the back of my legs and buttocks. I am worried that I have something more serious but I cannot find information about STDs with my type of symptoms. Please share any ideas you have. I visited the doctor (urologist) twice and he gave me painkillers plus antibiotics (ciprofloxacin). After 9 days of taking ciprofloxacin I went to a virologist and he have me Bactrim F which I have been taking for 5 days but still very little improvement. Pain has sort of moved more from testicles to urethra. Im very desperate and my body and mind are exhausted from this ordeal. Any help and information would be greatly appreciated.