I am a 66 yr old female and I have never smoked, I have had pneumonia 2 times in my left lung last time 6 yrs ago. I have congestion in that lung and crackles noises when I lay on my left side to sleep. Sometimes short of breath until I clear the mucus. I hear gurgle like sounds when I laugh deep. Had my first chest X-ray in 20 yrs and that was normal. Went to allergists no common allergies or asthma. Allergic to mold and dust mites. Am concerned since it is only my left lung. I sleep on my left side most of the night and have post nasal drip. Medicare may not pay for a CT scan since I am healthy and never smoked. Should I be worried?