I Like To Know If I Possible Have Lung Cancer.

I like to know if I possible have lung cancer. I have pain coming behind my ribs (behind my lower lung) for more than 10 years. I take Clonazepam to sleep or I get no sleep. I recently had x-ray and three times it reported a small spot on my left side. At first my doctor thought it was infection or nemonia and I was treated with antibiotic. But the drug brought on cough for two weeks before it subsided. I am a 76 yrs old woman, and I hate ct scan. I took one before in 2008 for the same complain to my doctor. The ct scan did not show anything or had no conclusion whatsoever but a lung specialist took a bronchoscopy, in 2008 and said I have bronchiectasis. Should I take the ct scan again? Currently, I don't have a cough. At my age, is it worth to have more ct scan?
tina