I have had these night-time attacks about three times a year for the past 10 years. I assumed they were panic attacks, but I was describing them to someone and they said they didn't really sound like panic attacks.
I only get them at night, and they wake me up. My heart rate is faster than normal but not by a massive amount, although the beat is very very strong. I don't really feel fear or panic, more total confusion, like I've completely lost track of who I am and my thoughts are all disordered. They can last for hours, and go in waves. Usually, I throw up and then they end, and I crash out into the deepest sleep and sleep for hours.
I don't get them at any other time, they are not connected to any periods of stress or bad dreams, just happen randomly 2 or 3 times a year. Beta blockers don't work on them.
Does anyone recognise this?