Urine testing for yeast isn't accurate, and probably wasn't done.
One of the common symptoms of prostate inflammation is the mucousy stuff you describe, and since your gonorrhea and chlamydia tests came back negative, it would be a logical next step.
You can have prostate inflammation at any age.
Aj
get a urine sample, might be yeast? I know when i went for a std test they tested my urine for yeast.
why would i need a prostate exam, i am 24 what will they look for?
It could be from dehydration, but that's not likely. Do you know if you were tested for white blood cells in your urine? Have you had a prostate exam? Those should be your next steps.
Aj