Does anyone else wake up in a panic from time to time? Not a rational\* one, but something before consciousness is present, this strong feeling as if you don't know who you are, where you are, what has meaning, and why you are alive?

I wake up and I walk around the house, and I wonder whose house is it, and why am I here, where no one loves me? (- I live alone)

Any theories for why this happens?