Sooner, it sounds like you had some sleep paralysis. I have had a similar experience several times. Feel like I am awake, but unable to move or speak and there is somethng "evil" in the room.One time I was asleep on the couch and it happened and my wife woke me up because she said she could hear me barely calling her name.
It's not an uncommon condition and accounts for a lot of so-called paranormal exoeriences.
http://en.wikipedia.org/wiki/Sleep_paralysis
In your case it's caused by massive guilt.