I'm a 25 year old man in good health but i've been having a problem with a very strong need to urinate. i don't have a uti.?

Look for irritants: There are substances that may cause bladder urgency and frequency: chocolate, peppermint, citrus, carbonation, tomato, spices, alcohol, tobacco, caffeine, splenda. If you have been overindulging in any of these foods, stop them as a test. Read about overactive bladder. Hold off on "pushing fluids" for a test. You may need to see a urologist about interstitial cystitis (not likely).

Bladder irritants: If you've been examined and for sure don't have any urine abnormalities then think of irritants. Coffee, tea, soda can all irritate. Cranberry irritates. Less likely something like interstitial cystitis.