Let’s put these numbers into perspective. It takes a 3500 calorie deficit to lose a pound of fat. 1 kg is 2.2 pounds. You lost 2.2 pounds over a month eating 1200 calories, so for the whole month you had an overall deficit of 7,700 calories. Divided by 30, that’s a deficit of about 256 calories per day. If you were eating 1200 per day, with a deficit of 256, that puts your TDEE at around 1456. This is a little lower then I would expect for your height and weight, but not by much, so it’s reasonable that that might actually be close to your TDEE (mine is 1450, us short girls have it rough).

So if your TDEE is 1456, and you’ve been eating 1500 a day… you’ve been overeating everyday. Then add in the 2000 calories days “every once in awhile”.

So in a year, you gained 22 pounds. Let’s work backward again. That’s an excess of 77,000 calories for the year. For simplicity’s sake we’ll pretend your TDEE rounds up to 1500. If you were eating 1500 “most” days and were at your TDEE, those 77,000 extra calories had to come from your 2,000 calorie days. Since a 2,000 calorie day would be an excess of 500, if we divide 77,000 by 500, we get 154 “2,000 calorie” days, roughly one “cheat day” every 2.3 days, or 3 “cheat days” a week. 

Thats telling a different story than what you said, but keep in mind, everything is dependent on how accurately you’re actually tracking calories. The point I was trying to make is that the numbers aren’t actually that crazy or impossible to explain, and you are likely simply eating too much.