Help i think im fat!?

okay i have an eating disorder and im not going to tell my mom.i look in the mirror and see fat.i dont trust people i know because they lie and say im not.theyll say anything to get me to eat.im 5,3 and i weigh 122.is this normal? am i overweight.if i am tell me what my weight should be.im 12 so that might change it a little