I feel thinner but I've been eating like a pig?

I'm sure I've been eating loads more over the past few weeks, and bad stuff too, loads of carbs and cheese. But I feel thinner. AND I'm on my period, which usually makes me feel fat. I'm not sure if I'm just deluding myself, or whether I have a problem, or whether you can lose weight by eating MORE? Can someone tell me why this might have happened?