A very hard journey ahead! Need your help!

Hello brothers,
I've had a very sad history with porn, that has made it hardwired in my brain, even though I'm only fifteen I've started to notice that I may already have already damaged myself sexually (slightly curved penis, premature ejaculation) due to EXCESSIVE masturbation nearly daily for years...

My story:
A healthy 8 year old who loved playing online games on computer, who started strangely enough trying to discover what's a woman body used the internet...
Wasn't until I was 10 when I visited my first porn site who my friends tricked me by telling me it has games.
After a month or so being amazed by that sinister new world, I started masturbating at 10, and I've noticed that PMO is a lot better than pure porn. I couldn't wait to leave school to go home and masturbate when I was only 10.
Since was geeky, I managed to hide my history and files, so my parents had no chance of catching me.
But the problem got a lot worse...
I thought to myself why only masturbate in the toilet, how can I do it anywhere?

And then I invented something deadly, I managed to masturbate while fully clothed and since I was still young I was able to curve it to the left while erect and masturbate.
you might be thinking what about the sperm, I figured something out too...
I used a technique to orgasm while holding myself (like before peeing) so the sperm instead of ejaculating returns to the urinary bladder, so after some time it gets out with urine.

Combining these two tricks I can now literally masturbate anywhere at any time.

THIS COMPLETELY RUINED MY PRETEEN YEARS.

I've even managed to masturbate in class, in the school bus EVERYWHERE.
Even when sitting with my parents at home in the living room.

Now after 5 years, I've been fighting this for one year now with constant relapses and I am very tired...

I have changed my school and I became more mature and ofc stopped masturbating in public.
Changing the school helped me so much, because after developing good social relations I've stopped feeling the need for porn, so it got limited to week-ends.
Which was great. But here I am more mature and aware than ever.
Since the summer vacay started I started returning to it in the days I was home alone (pretty much 5 times a week).

And I feel I'm going back.

Note:
I've a lot of good hobbies: I love programming, piano, judo...

Why I am here:
Because I've never shared this with anybody, and I cannot get professional help (since I didn't tell my parents), I have already a good experience with the forums, I've just started a streak 5 days ago but ended it today.

I'll really appreciate all your help, and I can help other people due to my early experiences.

Please, mainly I am very worried about my sexual health and I can never try it (my culture forbids sex before marriage) before maybe it's too late.
I'll be extremely thankful if I can get professional help.

Would really appreciate any help.

Thank you, and GOODLUCK TO Y'ALL!