Welcome to HealingWell. My heart goes out to you as I read through your post as I cannot imagine how awful this must be to go through. I would gues that your hematologist tested you for Factor V Leiden. Factor V Leiden is a common inherited genetic disorder that can increase your chance of developing abnormal blood clots (thrombophilia), usually in your veins. This genetic disorder can cause clots that travel to your lungs.
I do hope someone with simliar problems as yours reads your post and responds. I am here to support you emotionally. I do have the Factor v Leiden myself so I understand about lung clots however I have not had a clot so far.
Wishing you well,