Just to say up front, I've got a doctor's appointment tomorrow about this, but I wanted to ask anyway and maybe ease my mind. Not knowing is making me uneasy.

Anyway... About a week ago, it started burning when I urinate, also began itching INSIDE the penis all along the shaft and having a very slight discharge. My last sexual contact was 3 weeks ago, and I figured that I had probably gotten gonorrhea or chlamydia.

Went and got tested yesterday and got the results today--all negative.

The clinic that did my testing though it might be trichomoniasis, but they also suggested it could be a bad UTI, or a yeast infection. Unfortunately, the clinic doesn't test men for trichomoniasis, only women, so I couldn't find out there (hence the doctor visit tomorrow).

Does it sound like any of those? Or something else?

Sounds like a bladder infection, does it burn after you urinate as well?
Let us know how your appointment goes :)

Yes and when I take a pee it would stop itching now I have this discharge