Over the last 6ish weeks, I have been waking up suddenly in the small hours, with a horrible feeling of panic, claustrophobia and feeling I can't breathe. I try to remain in my bed, knowing it will pass, but sometimes I have to get up, put the lights on and stand at the open back door until it passes. I had a bit of a quiet freak out on a nighttime long haul flight literary a week or 2 before this started. Has anyone any experience of these feelings and advice on how to deal with them? TIA.