Hi,
Urinating several times during the day may be due to urinary urgency ( strong sudden desire to urinate), urge incontinence or due to urinary retention that may lead to constant dribbling of urine.
Hesitancy( trouble starting), loss of force or decrease urine flow and urinary retention or sense of residual urine ( don't empty all the time) may point towards an obstructive cause. An obstruction in the bladder outlet may present with symptoms mentioned above.
I understand you went through a lot of tests already. Any scans done ? Was further evaluation of the lower urinary tract done?
I suggest you discuss your concerns with your urologist once more. Other causes such as neurogenic ( nerve related ) and infectious causes have to be ruled out.
I hope I can help more. Keep in touch.
Thanks, I had the urdromdic test and I had a ultro sound on my stomach done.