I think you need a CAT scan to rule out Pulmonary Fibrosis, a CAT scan will show
a much better
picture of than any Xray. Is your doctor
a Pulmonologist? If not, make an appointment with one. Try to find one who is a Specialist with PF, a University Hospital is a good place to start. I had a regular Pulmo first and I lost more lung capacity by scarring being treated by him. Perhaps it is the anxiety, but lung function is nothing to fool around with. So, I say check it out.
Good Luck.