not well

I got really sick in December with pneumonia...caught a flu from grandkids and got sicker. I was getting better, then, in June, a bunch of us went to a graduation. 3 were sick with a cold. I caught the cold and went downhill really fast. My doctor only gave me doxicillin, which never works on me, and she refused to call me in another antibiotic. My sputum remained green for 2 months. I am not getting better. sputum is now white, but I can only walk a few feet because I cant breathe. I am scared of cat scans, I get really anxious, so I only had a xray. What can I do?