Im scared..

Im not skinny or anything but i am so confident with my body. I can still feel sexy. But i cannot eat. Im never hungry. The thought of eating makes me feel sick. I try to eat but its hard and can only manage a few bites. This has been going on since around march. I can go days without eating my belly wont even rumble. And if it does i still dont feel hungry. Since monday night (today thursday 13th august) i have only had 1 small sandwich and a chocolate bar. Still dont feel hungry! Im worried? Whats wrong with me?