I Believe I Have Bronchitis. I Went To The Doctor

I believe I have bronchitis. I went to the doctor 10 days ago and had a breathing treatment, got an Rx for cough syrup and inhaler. 5 days later I got a second RX fro cough syrup. I'm still coughing a lot. So I called the doctor's office yesterday and asked if I should have a chest x ray. A woman from the office just called me back and said the doctor will not authorize a "chest CT" until the bronchitis (that I believe I have) has cleared up. What does that mean? Do I have pneumonia? How do I find out?