Suggest Treatment For Non-productive Cough And Shortness Of Breath

I have had a non-productive cough for over a year. I do have GERD. I have had a endoscopy, broncoscopy, colonoscopy, CT-scans with dye and the only thing that showed up was some small nodules in lower left lung. I have seen a ENT Dr., Pulmonologist, and Gastroenterologist. Have tried many different meds. Breathing lung test was normal. Pulmonologist put me on a drug for allergies and possible asthma..no change. They also did a bravo study when I had endoscopy and when I coughed the numbers were very high. During this time over a year I also lost 30lbs., but since then my weight has been stable. I m only taking Aciphex for GERD, and Montelukast (sp) for possible allergy/asthma. Lately I have been having episodes of shortness of breath after doing simple chores. I have no wheezing, or any other symptoms. I also am very tired all the time. Do you think this could be asthma, or I was wondering if I should have a stress test as there is so much heart disease in my family?