Hmmmmm, let's see. I'll make a list.
1. School is giving me bs
2. My brother
3. Im constantly being pudhed down, mentally and physically
4. My friends are pretty much leaving me
... must I go on?
Honestly, I'm not gonna be that one asshole who says "oh, I've had it worse, don't feel bad.", but I'm gonna tell you this; I've been facing really bad issues for many years, and I've never tried suicide or self-harm.
The only advice I can give, is to fight back if you don't like it. If school is giving you BS; form a group of friends and solve it. If you're being pushed down constantly; stand up and push them off. If you're friends are leaving you; find new friends. Someone who leaves you, especially if it's for some bullshit/trivial reason; they are probably not your real friends. A true friend, or any friend at all, is supposed to be there for you, to help you in your time of need, to have a good time with you. If some 'friends' leave you for a dumb reason, leave them too, don't emotionally invest yourself in someone who didn't emotionally invest in you.
I can't stop you directly through a computer screen, but, please… if you're thinking of suicide or self harm, don't do it.
If you need to talk about anything, message me.