I have been coughing now for about 4 weeks. I occassionally bring up white mucous. never dark in color. no pink or red. When lying down I can here cracking sounds like mucous breaking up from my breathing. I have also noticed my stamina is way down and can feel my heart pound when i exhert energy. sometimes my heart feels like it is stinging and pounds like it is gonna pop out of my chest. I have to stop and breath heavy for a minute or so for it to settle. Any ideas what I am experiencing?