I Have Been Having Difficulty Breathing And A Feeling Of

I have been having difficulty breathing and a feeling of suffocation especially when laying down plus I have an area thatis over the right side of my heart or mid section of heart . no bluish color to lips and nail bed but I'm very overweight not a diabetic. I have an inhaler but it isn't helping do you know what could be going on? I also have lost about 20lbs in the last month due to change in diet.