hmmm...sounds like you were experiencing
hypnogogia.
This sort of thing used to happen to me pretty frequently when I was heavy into lucid dreaming, it's an in-between state of dreaming/waking kind and your eyes can be open and responding to light while your body is paralyzed from being in sleep mode.
When it would happen to me it could be pretty weird, because I would be in a lucid dream and then I would open my eyes and could still have dream material superimposed ontop of my external environment (that and I would always think there were people in the room with me and then I would do my *wake-up* trigger and lean forward and be alone in my room, haha).
+++The whole incubus/succubus phenomenon is believed to originate with hypnogogic states.