I had a ct scan with dye done. it said coronary artery calcifications are present among other things. i stopped smoking and switched to a mediterranean diet. should i be really worried about this at 22 years old? 65 270lbs. loosing weight is #1?

Yes, while at your age and in general such changes are not common, it is time to make lifestyle changes as you mentioned with weight loss as a priority. Next will be to get established with primary care/cardiology as you may benefit from cholesterol lowering treatment and need tight follow up. Your family history will be important as well in further decisions.

I would have someone else look at it. Sometimes people have a template and it slips through. Ask the same doc who read it to look at it again. 22 is too young to have coronary calcification.