Gonorrhea symptoms should start to improve within a couple days and usually pretty much clear up within a week. Gonorrhea resistant to the fluoroquinolone antibioitics, including levofloxacin (Levaquin) is increasingly common in the US. It is especially a problem in gay men (was your prostitute partner a male, by chance?), but is increasing everywhere. And many gonococci also are resistant to doxycycline. So the most important thing is to make sure you don't have persistent gonorrhea. (If you're not in the US, and especially if you are in Asia, you can definitely assume fluoroquinolone-resistant gonorrhea.)
If that's not the explanation, I'm at a loss. Co-infection with chlamydia is a consideration, but not in this case. Chlamydia is rare by oral sex, and in any case always responds to doxycycline and/or a fluoroquinolone like Levaquin. Another theoretical possibility is trichomonas, but that isn't acquired by oral sex. Most oral bacteria that might cause co-infection should have responded well to levo and/or doxy.
So all I can suggest is follow-up with your PCP as planned, making sure s/he checks for antibiotic-resistant gonorrhea. If that's what it is, you should be treated with ceftriaxone by injection. Otherwise, s/he probably will want to do a urine culture and perhaps check you out for less common infections, like yeast. But I don't have any other bright ideas.
Good luck-- HHH, MD
Thanks so much for your responce.