I thought i had bph/similar, went to the doctor, tests were neg. (no enlarged prostate, a dip test also neg.), what else can it be?

frequent urination: BPH would be unusual in your age group. Bladder irritants, such as caffeine, spicy foods, and alcohol, can cause symptoms of urgency and frequent urination. I would recommend eliminating these from your diet. A further evaluation may include a bladder diary.

bph: BPH is not very likely at 34 yrs of age. Depending on your symptoms, prostatitis is much more likely at your age. See a urologist.