Bump on tip of penis?

[huntbball11]

I have had a bump on the tip of my penis for about 4 yrs. now. The bump is small and it is located on the corner of the urination hole. I have seen a urologist and she said it was a puberty thing with the urethra and that the bump was just extra skin but idk..I overlooked it and have worried it was stds even though i have never had sex. It is sometimes red and enflamed but alot of times it is not even noticeable. I have had problems with urination pain and lack of masturbation. The lack of masturbation is due to pain. When i do masturbate things are fine but then 10 mins. after i feel the need to urinate. When i do i experience an excruciating pain that lasts up to 2 hrs. I also have had discharges when i pee as well. This is very depressing and i want to know what to expect when i go to the doctor. I am a 15 yr old male. Also are hair follicle bumps common as well on shaft of penis. And little reddish bumps under head of penis. Please HELP.