I stopped eating what do i do?

one night i felt fat and i felt the urge to go on a small diet so i slowed my eating and ate healthier and less than a week i wanted to stop the diet but my stomach cant handle the normal foods like my mom would make me a sandwich and i couldnt eat it i took a bite and thru the rest away i cant eat anything without wanting to throw up i have to chew gum to feel full what do i do?