I Have Tightness In Lungs When I Breath Out. I

I have tightness in lungs when I breath out. I am also fatigued. I was diagnosed 6 months ago with walking pneumonia and had a lung CT which showed ground glass opacity about 12 cm. It started with 18 cm and two nodules then after a round of antibiotics it was reduced to 12 and no nodules. I have the same feeling I had then. I visited the Pulmonary doctor this week and she said she didn't hear anything in my lungs but has ordered another CT, not until 9/4.