While you await tests, start doing anulom vilom pranayam(alternate nostril breathing) , to build up the lung function with extra oxygen. Keep your eyes closed, and it is 2.5 seconds to inhale, and 2.5 seconds to exhale. Do for one minute initially, and then build up your timing up to 20 minutes, twice a day.
February 22 ,2012
Hello and hope you are doing well.
The breathlessness could be due to cardiac or lung disorders. Breathlessness on exertion could be due to the decreased lung function. Since you have been exposed to a dusty environment, it would be worthwhile to get yourself evaluated for occupational lung disorders. In the meantime, follow your doctor's advice and continue with inhalers. To improve lung function practice breathing exercises and quit smoking.
Hope this helped and do keep us posted.