When I am tired, say 9:30/10pm my breathing becomes very heavy and it feels like it is an effort to breathe fully. This has only started happening recently and seems to be getting worse. I often now have to go to bed and fall asleep immediately. Sounds a bit funny reading that back as for most people it would be ideal, but I ve always been a very light sleeper so for this to be so full on is a big change, hence my concern.