Sorry, I misunderstood about the ID consultation.
Mycoplasma hominis and Ureaplasma urealyticcum don't seem likely to me. MH and most strains of UU are normal bacteria of the genital tract. UU may cause some cases of NGU (the research is controversial) but MH does so rarely if ever; and in any case, these always respond to doxycycline and/or azithromycin.
However, this makes me realize I forgot to mentione Mycoplasma genitalium. The problem with this is that it would not cause symptoms so soon after exposure. Still, MG can cause persistent NGU and sometimes requires different therapy than you have had, specifically moxifloxacin (trade name Avelox).
Metronidazole is only fair for trichomonas in men; the newer drug tinidazole (Tindamax) is more reliable. If you have only had metronidazole, you should definitely be tested for trich. Discuss it with the ID doc.
You should follow your ID doc's advice about testing and further treatment, but don't get your hopes up that these are going to provide the answers. My bet is still on chronic prostatitis or CPPS.
I apologize for not putting the following information in my post. I did see the ID Dr. about a week ago. He was the Dr. who put me on the 30 day of dioxy. He had me give blood as well as did a urine culture on me. I got results on the first of this month and with every other test that I have had everything came back negative, which I am pleased about. The ID Dr. did say that the following two diagnosis might be what it might be. He wrote it down a stick note but I cant really decipher his writing. One of them looks like Ureaphism. And the other is beyond my deciphering skills. Looks like Myplasm huminis. That's about the best that I can do in reading the writing. I did have the mertonizadole treatment which the STD clinic that I went to gave me for the trich.
Welcome to the forum and thanks for your question. I'll try to help. However, this is not a straightforward situation and neither this nor any other online source is going to be able to give specific answers. Even before you said you will soon see an infectious diseases specialist, that is exactly what my main recommendation would be. Here are some things that undoubtedly will be on the ID doc's mind and/or that you can raise yourself.
First, you can be sure you don't have a traditional STD such as chlamydia, gonorrhea, trichomonas, or a garden-variety case of nongonococcal urethritis (NGU), all of which would have shown up on testing and/or would have responded to the treatments you have had.
Second, as just noted, I doubt you have trichomonas. Still, I would recommend you be tested for it to be sure, preferably with a nucleic acid amplification test (NAAT). (I would be less concerned about trich if your treatment for it was with tinidazole than with the older drug metronidazole, which is less effective.)
Third, review the result of your urine culture for non-STD bacteria and discuss whether it should be repeated. Urethral infection with UTI bacteria, such as E. coli and many others, can follow insertive anal sex. The standard urine cultures generally are considered positive only if large amounts of UTI bacteria are present; the standard cut-off is 100,000 bacteria per ml of urine. Talk to the ID doc about whether smaller amounts of such bacteria might be present, so that the culture was officially interpreted as negative -- but in fact might indicate a continuing low grade infection.
Fourth and perhaps most important, you should be evaluated for prostatitis, i.e. inflammation of the prostate gland. Although not an STD in the usual sense, such prostate problems can follow urethral infection. Some prostatitis is caused by UTI bacteria, especially with low counts of bacteria as noted above. Others are classified as "nonspecific" or "nonbacterial".
Finally, closely related to prostatitis, you should be evaluated for the chronic pelvic pain syndrome (CPPS). This overlaps with chronic, nonbacterial prostatitis. In any case, many of your symptoms suggest this as a possibility; for more information, google CPPS (spell it out) and start your reading with the excellent Wikipedia article and information you can find from the Stanford University Dept of Urology. As you will see, CPPS often results from genitally focused anxiety, which has the physiologic effect of increasing tension in the pelvic muscles, which can result in symptoms much like yours.
In the meantime, don't be overly worried. Although your problem obviously started with a urethral infection (I would bet on UTI bacteria like E. coli), your current symptoms may just reflect residual inflammation, non-infectious prostatitis, or CPPS. None of these is harmful in the long run, either to infected men or their current or future sex partners.
I'll be interested to hear more after you have seen the ID doc. Consider printing out this discussion as a framework for discussion with him or her; I'll be you'll find s/he agrees with most of what I have advised.
Regards-- HHH, MD