Not able to take complete deep breaths.

I am having breathing issue for past15-20 yrs.When I run I used to go breathless.I can climb upto 3 floors comfortably,above that I start feeling breathless.I had this breathing difficulty 6 yrs ago.I had done treadmill stress contrast echocardiography,radiograph of the chest,spirometry test at Jupiter Hospital and the reports were normal.The doctors could not pin point the exact problem.They medicated me and said that it is anxiety.Now once again I have got the same breathing problem.I got the ECG,ABH test and BP checked,chest x-ray done but there was a slight congestion on the right side of the chest.I breathe slowly but not able to take in deep breathes,sometimes I am able to take a deep through my nose and mouth.When I sleep on my stomach at night sometimes the food comes up to my throat which irritates me and I get up choking.Sometimes I feel my stomach is bloated which continues for 2-3 hours.I have a nasal blockage but after using vicks it opens up but not able to breathe freely