@breakingbadmom, ER visits are certainly stressful! I hope you are feeling better. I always take findings like that outlined in your CT seriously, but that means following up. It doesn't mean that it's bad news. Our lungs are sensitive and can react this way to infection, inflammation, fungus, etc.
Have you had any recent infections, colds, or viruses?
You mention following up with cardiology, was there a recommendation to follow up with your regular doctor for the lung concern? They may help to put this into perspective considering the heart concerns too.