I’ve been binge eating but lost over 11 pounds

I’m really confused by this. My whole life and now, I’ve intentionally tried to cut down my calories to lose weight but best the end/middle of the day, i binge eat. it’s a cycle of eating 1600 calories one day then over 3000 easily the next few days. I’ve also consistently been going to the gym for a year now so nothings changed that much. I’m not exactly sure how but from when i weighed myself before i left for school and then now, it shows i’ve lost a significant amount if weight (keep in mind, i weighed myself with my clothes off and after a full day of eating) but it was still extremely different. I’m very shocked by this because it makes little sense to me and i know u haven’t been consistently on a calorie deficit.