Please help, I am worried

Hello friends,

I’m 17. I started masturbating at a very young age and have been doing it multiple times a day since then (I have a huge sex drive). I never had intercourse yet. I have to mention that I never masturbate by hand but prone, and it always works for me.

However, I recently felt like I’m starting to struggle to reach orgasm, and that the prone position is starting to become annoying because I run out of breath very easily before orgasm and I have to stop to breathe, which forces me to try 4-5 times before really being able to have an orgasm. I also noticed that I was less horny and that my erections were not as long and powerful as they were a few weeks/months ago.
Please note that I am currently undergoing an antidepressant treatment (sertraline). So I tried to Google the side effects of the meds and found that it could be the reason why.

Then I tried searching things about prone masturbation to settle my breathing turn-off issue. I’ve always been ashamed of not masturbating “conventionally” and thought that I was the only one using this method. After seeing that it was also used by many other men, I found articles pointing literally every of my problems and linking it to prone masturbation : curved penis, erectile dysfunction etc.. and I started to worry a lot.
After reading a bunch of articles saying that I should stop prone, I gave hand masturbation a shot. I can feel sexual pleasure through it, but it seems I can’t reach orgasm with this method, I’ve done it twice, for more than 20 minutes each time, and no matter how much pressure or speed I put into it, I don’t manage to finish.

Can someone help me ? I am really worried because if I have to quit prone but can’t have orgasm with my hands I don’t know what to do next. Also I worry for intercourse because the articles online say that it’s less powerful than prone.
Thank you very for your time.