What do you think is going on?

[helpseeker12]

Last july I recieved oral sex from a woman. About a week later i had an intense urge to urinate, often resulting in little urine. I went to a general doctor and they gave me cipro, although no bacteria was found in my bacteria culture. The cipro greatly reduced the symptoms. I had no discharge or burning/pain during urination, just excessive urge with little urine. After the 10 days of cipro, the symptoms returned, although not as severely as before. There is just usually just a lingering feeling after urination or in between urinations. I was tested for chlamydia and gonorrhea. Both of these test were negative. Later in october, the symptoms were less severe, but i still didnt feel right; I would notice a lingering feeling in my urethra. I went to an urologist and was given doxycycline. This didnt really help the symptoms any. After this, they looked into my bladder through my penis and everything looked fine. Once again, no bacteria was found in my urine or after a digital rectal exam. I have also been tested for HIV and am negative. It is 6 months later and my symptoms are not horrible but are nevertheless still somewhat there. Is it possible I have some other sort of STD? The partner said she had been tested earlier that year, and was not experiencing any signs of STDs. I was thinking of possibly trichomoniasis, but it seems that this is not spread through oral sex because it can't thrive in the mouth? Any other ideas as to what I could possibly have? Sometimes I feel as though I feel my urethra spasm and give me an urge to urinate. My urologist says i have no bacteria and my insides look fine, so I should be fine, but it still isnt right at times. Does it seem like i have prostatitis, urethritis, etc. or worse an STD? Thanks