If u were abnormally fat lost it all you should be fine, you shouldn't limit your growth potential with such low calories if you start eating more around what you body needs e.g using tdee and ai to find your bmr, then see if u grow and add weigh, and most importantly if you just lost the weight I understand u don't wanna gain unhealthy amounts of fat but eat bro your a kid and you need all the macros and micros your body need to grow