When it's busy, this kind of stuff happens

So, I enter the patient's room and leave my cow by her bed. I left because her inhaler was in another cow. I walked to the other cow. I opened the other cow. I took the inhaler out of it, and returned to my patient's room. The curtain was pulled around the bed. A nurse was behind the curtain.

I said to the nurse, "Is my cow back behind there with you?"

She said, "No!"

I said, "I just left it there. Where could it have gone?" I said this in a facetious manner, knowing she must have moved it.

She said, poking her head out from behind the curtain, smiling. "I don't know where it is?"

I walked out of the room. I looked at the room number. I realized I was in room 9. The room I left my cow in was room 11. I said, "Well, it seems I'm in the wrong room."

She laughed. She said, "It seems you need to drink some more coffee."

"Agreed!" I said.