I have the same feeling in my chest, except it hurts when I take a deep breath in. I have had multiple pulmonary embolisms (blood clots) which have left my lungs scarred. I also have nodules (they don't know what they are maybe the lupus or something else) they are just keeping an eye on them. If you feel short of breath, VERY fatigued, and it hurts when you breath, you should go to the ER these are the signs of a blood clot! The test your doc ordered sound like he's on the right track. I will keep my fingers crossed for you!!