Good morning @helena4000. I have not had your experience however I know all about shortness of breath that accompanies lung cancer. I re-broke a rib as a result of lung cancer surgery and when the rib hit my chest wall the pain was incredible. Before my Xray the doctor thought that my lung might have collapsed. When this started it must have scared you very much, to say the least. I am so happy when patients stand up to their doctors for good healthcare. I applaud you for this. Here are two sites that you might find helpful, if you haven't already. Good luck!
https://www.healthline.com/health/bibasilar-atelectasis, https://www.mayoclinic.org/diseases-conditions/atelectasis/symptoms-causes/syc-20369684