Just wanted to chime in with some support and say that I admire your courage in starting this thread.

The relationship of sports psychology, eating disorders and sports nutrition is one that needs to get more attention.

If you are a teenager, your body is still developing. That means your ideal weight and other stats related to your performance is also still developing. No coach and no amount of sports science can say for sure where you will perform the best, especially if you intend to compete in this sport for a long time. Yes, there are guidelines, but you also need to trust your own intuition.

I've been through the experience of unintentially losing muscle -- due to extreme stress -- and it can definitely take a lot of time and deliberate work to regain that muscle and be in a good place.

Be strong, and be good to yourself!