Could Too Much Coral Calcium Cause Misscarriage?

I am 44 and i was 11 weeks pregnant and lost my baby one week ago. I visited vitamin world looking for specific vitamins for our pregnancy (as i have always been a big vitamin taker, throughout my last pregnancy too), and it was suggested i take a coral calcium supplement (1500 mg/daily intake requirement, in one capsule) since i do not drink milk on a regular basis. Within 3 weeks, i began spotting and then misscarried. Looking back, it seemed as soon as i took my vitamins, i would begin cramping, and the spotting would increase. I have three healthy children ages 25, 20 and 6. My doctor said i am not too old to carry a child, as my health is excellent and he gave no reason not to try again.