i want to cry every time i see someone ask this
im 16 years old too and have been going to the gym for a year now. (I HAVE STILL GROWN. MY GROWTH HASNT STUNTED). Im even one of the weight lifting maniacs, not some cardio guy and im still 5'10" ( 180 cm or something) compared to last year where i was 177cm .
My friend however has been going gym for much longer but he started out much shorter than me. He is about 10x stronger than me but his height has not changed much. He was already pretty mature to start with (facial hair at 14) so i doubt that he wouldve gained much height.
I think gym is really good and that you are still likely to grow alot both physically and mentally. Do not listen to others who discourage you. Do this for yourself!!!