Please do not be afraid. I too have microcalcification in my normal breast. It has always been that way. But since I have had breast cancer in the right (that was not a result of any calcifications), they check it every six months just to be sure the calcification is not clustering. So far it hasn't. But it is good to have it checked routinely. I really do not like it when a doctor puts a statistical age to any breast condition as anyone "really" can have any and all breast conditions at any age. The women here are good examples of that.
Having said that though, you really shouldn't be worried. Calcifications in the breast is not unusal and it does not always mean cancer will follow. Just keep getting your mammos when the doc suggests.
Two are better than one, because they have a good return for their work: if one falls down, his friend can help him up. Ecclesiastes 4:9-10