Confusion

I started reading a book on Sunday and then I put it down for a few minutes and now I can't find it. I looked and looked last night, but it seems to be gone. Which is strange because my apartment is not that big. There just aren't that many places it could be. I also seem to have hit my head on something at some point on Sunday, but I can't remember what or where. All I know is there's a small, sore bump on my forehead. And I vaguely recall bumping my head, but I really can't remember where I was or what I was doing at the time. I must be losing it.