that fact that you lost that much weight in less than a week tells me that it's mostly fluid and not actual fat or muscle. it would be impossible to figure out the reason for this based on the information you have provided. the best thing to do is to let your parents know and see your primary healthcare provider to find out what is going on. if it is something like diabetes which can cause sudden weight loss the sooner you get help the better. the scary part is not knowing. don't delay!
i'm 16 and i eat a lot. i've gone from 113lbs to 99lbs in less than a week. what's wrong with me? . i do not throw up. and i dont exsercise much just a few sit ups here and there. please help. im very scared.