Blood in urine, groin pain, abdomen pain after unprotected sex, help

I had unprotected sex, the next day my testicles hurt and I had lower left abdomen and groin pain. I went to the doctor and took a urine test, he said I had blood in my urine. I took some antibotics, which seemed to help. I still had pain in the abdomen and testicles, so I went back. Took another urine test, still had microscopic amounts. I went to a urologist and he did a ultrasound and said everything looked normal. He gave me more antibotics, which seem to be working. I still have groin pain in the pubic area and lower abdomen pain. I know you can't diagnose it, but can you give me some ideas what may have happened, I am really concerned?? I also had a blood test which came back neg., I am going to take another one in a month.

Thanks