My doctor started on me on nifedipine for my fast heart rate. I soon noticed that I have become very constipated, is this related?

You bet it is related.

Calcium channel blockers like nifedipine are notorious for causing severe constipation. You have two choices, ask your doctor to switch the drug or you need to be on continuous medications that help loosen your stools. 

Most people need to go off the nifedipine as the constipation can be quite severe. Do not stop the drug until you see your doctor. In the meantime, drink ample fluids, eat a high fiber diet and take lactulose twice a day