Ive been dealing with shortness of breath for about 5 years and all my tests like PFT, ECG, CT thorax, chest X-rays, 2D echo, and others came back normal. Ive even had them repeated in 2017 and 2019. Ive seen a lot of pulmonologists and cardiologists but nobodys been able to figure it out. It used to only bother me at night but now it happens during the day too. Even sleep meds arent helping now. Some doctors thought it was tension or weakness, but I'm quite active, exercising and doing yoga and pranayama daily. Night times are really tough and sometimes I can't sleep at all, even with meditation or taking stalopam plus. I'm only 21, so its really worrying. What do you think could be going on?