Over-eating on your period

Megan
So, I have a pretty normal period. Lasts 6-7 days, almost always on time, medium flow. 
I have never had anything too bad. But recently I've been trying to lose a bit of weight and I started to write down everything I was eating in a food journal. It was going really well for a few months before I noticed that I was eating far more than I should when I was on my period. I try to eat 1,800 - 2,000 calories a day but when I was on my period I was eating 2,500 - 3,000 calories and I was putting weight on instead of getting rid of it. Does anyone know any ways to stop over eating, Much appreciated.