My first thought is you are reducing your calorie count too low, 1200 is borderline starvation for someone of your size. My second is that you are making a mistake doing all the cardio in an attempt to lose fat, cardio is in last place in the fat loss equation, diet (nutrition) is first, strength training is second and cardio is third.
I suggest you concentrate on strength training, adjust your daily intake to match your level of exercise and fat loss goals and back off on the cardio.
It is called WORK-ing out for a reason.
I said getting fit was simple, I did not say it was easy.
Cardio burns calories, strength work burns fat.
Eat well to lose weight, exercise to get fit
You can not build a six pack using twelve packs
Often when we seek a magic bullet for fitness we end up shooting ourselves in the foot.
"I think calories are little germs in food that all moms are afraid of" Dennis the Menace