I am experiencing pain in my chest that centralizes around my left breast. It is a constant dull pain, but gets stronger at times. Sometimes it aches when I breath, but not all the time. 2 nights ago, I woke up from a sound sleep with my heart pounding and fluttering and it lasted about 5 minutes. I am a female, 54 years old, in overall good health, but I am obese. I also have a cough that never went away when I was sick with the flu in late January, that seems to be worsening now.