Suggest Treatment For Pain While Urinating

Hi, may I answer your health queries right now ? Please type your query here...hi. Am 14 years and i have some blockage on the tip of my penis. Urinating is very painful as the passage is very tiny. I wad circumcised when i was 10 years old. The tip was not so big but it seems to get smaller with time. What could be the cause and what treatment should i seek? Brian