Am i eating too much?

I am 5'9 female, 19 years old and i weigh 135 pounds, down from 148 last october. I have been eating around 1400-1500 calories a day and i do 30 minutes of cardio on the elliptical machine at least 4 times a week, sometimes every day. I break a huge sweat and work very intensely! i am trying to lose 7-10 pounds before the middle of may. I eat healthily, no refined sugary foods and all the right stuff but im worried that 1500 calories may hinder my weight loss..what do you think?