Happened to me in London once.

Woke up during the night because of a red light flash. Was confused but then "realized" that the ceiling was slowly moving down. Panicked, crouched on the floor and out of the room (in boxers). At the last second put a foot to prevent room door from closing. Was sitting like that, 95% in the hall, for a minute or so, realized it was a weird dream/sleepcrouching and went back to sleep.