It is possible that your
asthma truly has been precipitated by
second hand smoke and, equally possible that your asthma might be of the subtype of asthma, in which the airway obstruction to breathing out has become fixed or irreversible, and the irreversible airway obstruction, mimics that of COPD.
Pulmonary function tests (PFTs), especially with lung volumes and a carbon monoxide (CO) diffusion capacity might enable your doctors to make a more specific diagnosis.