Why Am I Such A Complete Failure?

I ate today. I had an apple and a subway sandwich. Not like the good kind of subway sandwich with lean meat and veggies. The bad kind. I looked it up on Subway's website, and with the apple I ate around 900 calories.

What is wrong with me? I did so well last time. Why can't I do that again???

I seriously hate myself. Why can't I have more self control?