Sounds a little like lucid dreaming. I have dreams that change like that when I seem to doubt what's going on. (kinda like when you told the hottie you were married.) It's kinda weird when it happens, since the brain seems to be like "alright, here's something even more odd for ya"

I'll give one of the less weird examples - and believe me I have some really strange ones. I was being attacked by something once, fought back saying "this isn't real", and then my dream switched to my being in an airplane made of cotton candy and bubble gum being flown by a spider.

Yes, I have issues, LOL!