(((hugs))))
I am very sorry to see that you're in such pain and intense fear. I can relate a lot to your loneliness, major depression, and panic. I've been there as well. I was a huge loner throughout my childhood, which didn't help my perspective towards life any.
Your post implies that you aren't seeing or talking with anyone to help you through these tough times, is that right? Have you tried getting in to see a T? Perhaps when school begins in a couple of weeks, you can talk with your school counselor about your misery to get their assistance?
I do know that schools are trying to be much more active in helping teens work through their feelings of intense loneliness, fear, and depression nowadays. I'd certainly advise you to try talking with others at school, to make a connection or two. Hopefully, these connections will go on into life out of school as well.
Do try to get in to see a T, as well, and share these things that you're struggling with.