Late for something I can't remember

"I knew I was late for something important, but I couldn't remember what it was. I was running through my house looking for my shoes, and somehow none of them belonged to me. I finally found one shoe under the kitchen table, but when I put it on, it was the wrong size. Then I was suddenly standing at a bus stop with no idea where the bus was going. I could see it coming, so I started running, but my legs felt strangely heavy. The bus passed right by me, even though I was waving at the driver. Next thing I knew, I was sitting in a classroom. Everyone was already taking a test, and the clock said I was three hours late. I tried to explain myself, but my voice wouldn't come out. Then the teacher looked at me and said, "You've been here all along." I woke up confused and immediately checked the time."