I am a 13 yr old girl who is 5 feet tall and every fall at school (all of October) I become extremely tired and nauseous. Sometimes I fell so ill while standing I may break out into a sweat, go quite pale and sometimes lose vision (goes black/ purple then goes blurry stays this way for aprox 45 seconds after sitting/ lying down) however after eating some sugar and drinking a fruit juice I feel better... Until the next day. In October I do not change my diet or gave any more/less physical activity. Many of my teachers and friends suggest I am anemic but what do you, a doctor think?