Hunger overrides sense of fullness after weight loss

I don't know about the hormones, but this has been my experience. I recently started the 5:2, where I eat normally for 5 days and 500 calories for 2 days. I should note that eating normally for me means 1400 ~ 1500 calories and low carb. The 1500 calorie days seem harder than the 500 calorie days. I guess the calorie restriction is causing hunger to carry over even on days when I eat what should be satisfying. I don't remember experiencing that before, but then I have never really tried calorie restriction.