Hey cat - really good to see you!!!
Interesting subject you bring up. I'm glad Billyj brought up the sleeping pills because i know there are really high incidences of this in the US with people even driving in these halfsleep/half wake zones, and then the next morning can't find their cars and so forth.
But if there are no meds aside, then it would be a dissociative state like Sky said.
I, too, used to sleepwalk/talk/climb... but it was always just that. Only one time do i remember being slightly lucid in the dream and (as i walked past my poor confused mom) i said "I'm the leader but they're not following me!" i guess i turned on the hall light, went down the stairs... i do remember waking up downstairs and looking at all the fog outside. I said "look at the pretty fog....!" fell back asleep (evidently) retraced my steps, passed mom again and this time went and fell into her bed. @_@ Oh, i do remember one other one in college where i was dreaming there was a party at the end of the dorm hall. I was going there when I woke up with my hand on the door nob of my door - going what am i doing!?!? Good thing i woke up, or i would have shown up at a stranger's door, in my nightgown, with no key (doors lock automatically) and no id, at 3am. Thankfully i seem to have finally grown out of this!

Sorry, i digress - back to you. I have read that people with DD/DID will do that - go to bed, another self wakes up and does things, then next morning the usual self can't understand what happened. I find it interesting that you are mostly aware of being up. I hope you find more info as you go along!

I'd never heard of exploading head! I also for years had the thing where I'm just about to fall asleep and then I'd jolt awake because I had the feeling like i was falling in blank space - and then would feel like plummeting to the floor. Freaked me out!!!

(((((((((((((((Cat!))))))))))))))))))