Am I at risk of becoming Anorexic?

A few months ago I went through what I would call a faze where i only ate dinner and even then i felt guilty after I ate and i went for a 45 minute walk at least once or twice a day and this went on for a month then one day I binged and i went back to eating junk food again. But now about 2 days ago i've been looking at my friends and thinking how fat I look compared to them. So again i have started skipping breakfast and pretending to forget my lunch when i go to school. I only eat dinner without complaining because at least then my parents and family will not suspect anything. To me i think of it as a diet but I have drastically cut out a lot of the food I eat because I want to lose weight fast and be skinnier then my friends for once. Help?