Extremely disoriented following a short nap

At my sister’s house … I just drove up here to visit with my sister and mom for Mother’s Day this morning. I was tired all day, and with a little quiet time here I decide to take a nap on the couch. I fall sleep almost immediately.

I don’t know what I was dreaming about, but apparently a loud noise woke me up. I sit up on the couch, looking around, and there’s a woman standing by a pantry closet, looking at me. "This noise didn’t wake you, did it?", she asks. As I look at her I say something like, "I don’t know." The truth is, I don't know what woke me up, and I also don't know who this woman is, or where I am.

I sit back in the couch for a few moments — possibly a minute or two — until I realize I’m at my sister’s house, in her living room, and the woman that asked that question is my mother.

I was dreaming of something, but what? And why am I so disoriented?