This is a very complicated question and difficult to answer without all the medical details.
But, first and most importantly, you should not hold yourself responsible. Although we are very concerned with air pollution of any kind, her condition appears to be unusual and does not appear to be due to the dust from your renovation.
There are a lot of conditions, which can cause bloody sputum - including lung cancer, infections, heart disease, and others. Small "aneurysms" in the lungs is one cause - but remember that your doctor is probably trying to make this understandable to you, and I can only guess what the medical condition might be. The lack of production of red blood cells is possible, but again there are multiple causes. I suggest you get more information from your doctor.