Hey there, so I'm 15 and use to weigh 135 pounds. I'm 5'7, but now I weigh 123 pounds. There is no reason why I've lost this much weight. I'm eating the exact same way, I'm not excersising... so what is it? Am I sick or something? I've already hit my growth spurt when I was 12 and haven't grown much in the past year. I just don't get it. Any help? My parents are worried about me, and they think I'm on drugs cause of it.