Breathlessness. I consult this problem.

Hello Doctor Im feeling breathlessness from last 5 months. I have consulted with pumologist , ENT specialist, Allergy and Immunologist but all resports are normal and doctors are saying nothing to worry its because of anxiety they r saying ,but im not so much that in deppression in my life so how can be it related to anxiety. im tired of taking tablets but now from few days i have observed that when i burp up that after i feel better so Dr. Do you think this problem related to  GERD when suddenly gas trying to come out and stuck inside that time i feel more breathlessness and this problem occurs anytime. Dr. Please help me out of this. Which medicine should i take or to which speacalist should i consult this problem .