Thanks for your query. The diagnosis of COPD requires breathing tests, whereas a chest x-ray may only suggest this medical problem.
With chronic bronchitis, the person coughs up mucus from the chest most days (at least for 3 months) over at least 2 years. If you do this, then you do have chronic bronchitis. With emphysema, the main symptom is shortness of breath with activities. A breathing test called the diffusing capacity is lower than normal in those with emphysema. Some individuals may have components of both chronic bronchitis and emphysema.
It is possible that your doctor may not know the answer to your question if he/she has not ordered pulmonary function tests (PFTs) – commonly called breathing tests. I suggest that you ask your doctor about ordering these tests.
It is likely that your breathing difficulty is due to COPD, although heart disease may also cause someone to be short of breath. PFTs are “key” to make sure of the correct diagnosis. If you do have COPD, it is likely that “not being able to keep up with peers” is due to the narrowing of your breathing tubes. The narrowing makes it hard to get all of the air out of your lungs when you exhale, and the “trapped air” affects the ability of your breathing muscles (the diaphragm) to work properly.
I encourage you to quit smoking and to ask your doctor whether inhaled bronchodilator medicine(s) may help you breathe easier assuming PFTs do show narrowing or obstruction. This information and much more are available in my book COPD: Answers to Your Questions (published February 2015) which is presented on my website.
Donald A. Mahler, M.D.