you should be eating normal, your body is literally still growing. /omfg you're only 12???/ too many carbs is bad for you (rice, omfg. i'm asian and rice is like half my meal sobbing) if you starve yourself (which what it sounds like ;/) you're not really "losing" any weight because the way you're losing weight isn't healthy and you can easily gain it back vs. if you eat healthy/exercise/etc. - you can keep the weight off for longer.
be healthy bby <3333