You're only 17? You're very articulate for your age.
My daughter is a teenager and I know she has a lot of sadness--lack of confidence, etc.
However, even though I struggle with my own demons you are so young; and remember you have a purpose in this world. Being a young person in this world at this time is incredibly hard.
Journal; write your thoughts down. That has always been theraputic for me. Best of luck.