What has happened to me?

[ProstatisHogaya]

I am a 15 yrs old Indian teen and I Masturbate a lot. I have been masturbating since when I was 13 yrs old. At first I used to touch my Penis and masturbate. But after some time I didn't got erected when I masturbated while touching my penis with my hands. So I just used to shake my Penis while my undergarments were on. And till now I do the same until last week. When I was masturbating 2 times a day and one night when I ejaculated i felt pain. And it seemed like the pain was when my sperm was passing through whatever pipe it passes through. After that i did not Masturbated for 8 days and on the 9th day I did it again and again I felt the pain. This time I also felt discomfort in my testicles and I was really scared. After one day, I could help my self with it and I again masturbated and this time too i felt the pain alongwith a bit back pain too. Since the oain started I have Masturbated 5 times and always felt the pain. I really don't know what has happened to me and I can not tell these things to my parents. I would also like to add that I have uncircumcised penis and I am unable to open it. It is tight. Whatever has happened to me, can it be cured without going to the hospital? Because I again want to Masturbate and I can't myself with it.