Did I really gain 11 pounds after my binge?

You sound like me .. I also binge, it's really annoying. To be honest the thing that helps me is trying out new foods and finding healthy foods that taste good. I used to be the type of person who would choose chocolate over anything, where as now it depends on how I feel and I often feel like a fruit or veg. juice instead or a salad or certain meal. You have to start to enjoy healthier foods so that eating them doesn't feel like a chore. In terms of the 5kg's..it prob just because you stuffed yourself and you may have been drinking a lot of water and have water retention. If you eat lightly for a few days (no carbs...salads and fruit etc and a lot of cubers..they're a duretic and will make you pee a lot) then you will lose the water weight. I can gain or lose about 3kg's within a few days just based on whether I'm stuffing my face or watching what I eat :p