Why the binge??

It is now 7:09pm. I ate plenty of food for dinner, I was not hungry afterwards but I had a piece of brownie, 3 oatmeal cookies, and 2 rice krispie squares. The worse part is I could keep on eating, the good part is I did stop. But why did I start? I feel like a big old stuffed failure. I am so stupid, I am so stupid, I am so stupid!!!!!