I don't know how much to eat everyday!!

I'm a 15 year old girl that is 5'3" and 129 pounds.

I have an athletic/muscular body (my legs are REALLY muscular), but I've got some fat that I want to get rid of. I really want to be 110-115 pounds.

I weight train and have field hockey basically 5 days a week. I try to eat anywhere from 1500-2000 calories, but someone told me that eating that much is not enough? Also, I have not been losing weight, even though I eat healthy and exercise.

I burn about 2,500-3,000 calories during the week (active days).

How many calories should I be eating??? I don't want to harm my body, but at the same time, I want to lose weight.