How much would I lose and is it good?

I do kickboxing for 50 minutes then Pilates for 30-40 minutes. I eat 1200 calories (I'm not starving myself,I just feel full after a small amount). I also don't eat any candy. I'm a teen 5'6" female and weigh 140 lbs. How much weight would I lose and is it healthy?Should I change it and why? And is it better to do pilates every day or everyother day?