I am experiencing breathing shortness even with minimal activity like taking bath, walking 100 mts, or any other physical movement. Its been more then 2 months that it started. It gradually dragging me to weakness and less energetic. I am now feeling little effort in breathing while resting pose as well. What kind of doctor/specialist should I consult for this problem? Male, 29, 5'3'', 55-60 kg, non smoker.