Me: Male, 25, living healthy. Taking only Vitamins, Omega3, MSM and no other weird supplements.

So, I've come here with a few questions!
About 2 months ago I started getting som acne on my upper back, as I work out alot, it's normal sometimes.
However, this exploded into getting acne ALL over my back, huuuuuge inflamed acne. It really hurts just sitting on a chair nowadays!

Now it got even worse, out on my shoulders+upper arms. But they are not as big and inflamed.

I've never had problems with acne, and now I've gotten it at the age of 25, and it's sooo freaking much. Everyone I show my back is like "WTF!??"

Doctor subsricbed me Tetralysal + Finacea/Epiduo, it didn't help at all.
Now I got subscribed Roaccutane. I'm really scared of this strong medication, and I'm not sure if I want to start it. I'm scared of hairloss especially. Had some thinning hair already from all the Tetralysal (I had Perioral dermatitis since I was 20 and took it now and then during 4 years)

All the tests they did on me was checking my blood (due to if I can do Roaccutane) like can't this just be something hormonal since it started at the age of 25? Feels like they didn't really test much before giving me such a "bad" medicine...