Last night I laid down to go to sleep and instantly saw HI's. I was walking up some rock built steps (following some people) in the image I tripped, then my feet/legs which were crossed at the time shook really hard and woke me up. I'm talking in like a matter of seconds. It appears there is not time limit on how fast a dream can appear and how fast SP kicks in. Even though I jolted awake, I could have kicked my leg much harder I bet.