Do I have an eating disorder?

Im 16 and Ive been obssesive about my weight for a few years now. It reached a peak a few weeks ago when I realized dieting and exercise wasnt enough to make me lose weight. Plus Ive been super stressed out and depressed. So I started to starve myself. I do it to help me get my mind off stress and other painful things in my life. Its my escape. I havent told ANYONE. I dont want to theyll think Im crazy and try to get me to stop. I went a whole week without eating anything and I lost 10lbs. In ONE week. Obviously this has me hooked so its all i think about 24/7 and I freak when ppl try to make me eat. But after a week or so I start to crave food so i binge-eat. I puke sometimes but not always. I cant eat normally. Mainly I just dont eat. And I feel happy when I dont eat. When I do eat I feel soooo depressed and down I begin to hate myself for eating. This is a cycle and I feel out of control like I cant stop. Is this an eating disorder or just stress or something? Please, please help.