I'm 15, Male, Circumcised. My Meatus Began Being Irritated And

I'm 15, male, circumcised. My meatus began being irritated and inflamed. I thought that it was chafing from underwear but I noticed that my urethra was closed shut even though the meatus lips were open and swollen. I than began urinating every 2 hours or less and it was hard to start urinating because of closed urethra. Pee was very watery but I haven't been drinking enough water to pee so clear so often. Right under the head on the bottom of my penis also hurts. I have no sex drive (although I've never had sex) the stream is strong but does not last very long. What should I do?