Could this be called sleep paralysis?
It happened to me after having a very faded and short lucid dreaming that I woke up and couldn't move...I heard already about SP before this happened and I was freaking scared! I didn't actually tried to move anymore when I saw I couldn't...I was trying to imagine of nice things and not think about scary stuff.
It lasted like 10 seconds...
When I was younger I dreamed Chester from those cheetos commercials. The dream suddenly stopped and I heard a loud buzz (like in SP symptoms). I was still dreaming and yet feeling those strange sensations.
When I woke up it was all right.