First, welcome to the forum.
Okay, so yeah the teen years are rough, confusing, and you've done some good things and bad things (like cheating). Everyone expects you to know what you want to do with your life at your age now, and it sucks because sometimes you just don't know. I say keep with trying different things until you find something you enjoy. Stop going to doctors who are pumping medications into you, what it sounds like you need is to talk to a counselor, not like a medical one or shrink, just someone who might be able to help you figure things out. Some employment programs have people there that can help you with that, sometimes even some colleges will allow outside people to come in and see them to discuss what they might want. Of course they'll try to get you to enroll in their school.
I didn't really know what I wanted to do with my life at your age either, and my mother wanted me to pick something practical. So I ended up taking Computer Programming and System Analysis and found out that I really didn't want to do Computer Programming. I've worked at a newspaper, a family shop, a furniture store as a delivery manager and sometimes sales person, and now I'm a manager of an equipment rental shop. I actually enjoy my job now even though I'm not a mechanic and never had any interest in that, but I do it anyway.
What I'm trying to get at here is that you never know where life can take you and that is part of the fun of it. You never know what you might end up doing, but you do need to stick with something longer than what it seems you have. You might not like it at first but that might be just fear and anxiety, it goes away once you get comfortable where you are. You could end up leaving a job you could have enjoyed and excelled at.
Can I ask you something? What made you spiral downwards at 14? If you used to be a social and happy kid something must have happened to change that. Understanding and dealing with what happened or changed you could be the key into turning things around for you.