you can't trust something like myfitnesspal to adequately gage the calories you need for weightloss. there's too many variables and it always undershoots your needs ESP if you exercise.

you shouldn't be eating less than 1500. 1500 cals is what they give coma patients. if you do then it's very possible you'll start overeating/binging.

also if you're exercising then building muscle mass will increase the cals u burn just by existing (this will be minimal since yr not a professional athlete/trainer but it still can add up). try weight training even if you can't do high intensity cardio yet