My breathlessness started about a year ago, which I ignored and I ended up in hospital with suspected heart failure at Christmas. My doctor put me on oxygen at night which I now use in conjunction with a CPAP machine, nights only. I'm still awaiting pulmonary testing, even though the hospital cardiologist and my own doctor have written asking I be given an appointment. My breathlessness is so bad that I have to lie down in the afternoon with the oxygen. I don't go out as I'm too breathless. I am getting worse. I wanted to ask if anybody has experienced an awful feeling when you awake. I get it if I am napping in the armchair and I will suddenly awake with an awful feeling, which quickly passes off. The feeling is like feeling drained and as if I'm going to die or pass out. I've only had it once when I was on the oxygen, but get it quite regularly if I fall asleep sitting up, which is often as I'm always falling asleep. Tired all the time. Could it be that my oxygen levels drop too low?