i really need your guys' help...

Try not to make bad decisions....but honestly, I've made several in the past week. We all have bad days/weeks, so just try not to let that happen again. And if your best Friends hate anda for how anda are changing, then that's their problem. They should appreciate anda for who anda are, not hate you. But sometimes they just act that way, even when they appreciate anda for who anda are. So don't let that bother you.

Listen to music.
As the old saying goes..

Just focus on what makes anda happy =3

Follow your morals. Do what anda know is best.
Every pain and stress is difficult, and hard to overcome. But it always subsides, and the storm always passes, and you're always stronger when it does.
Get your parents to trust them, tunjuk them that anda can be trusted and that anda learned from your mistakes and bad decisions. If your Friends leave anda for it, then so be it. If they leave your for changing in the first place rather than supporting you, then they aren't what anda need to begin with. It may be lonesome, but being alone and having strength in yourself is far better than being with Friends who beat anda down and feel worthless.
It's hard, it's difficult, and it's hell, I know. But anda can make it out of this, and anda will get stronger from this if anda let yourself.