Awkward Conversation

Whilst sitting in the ICU writing a progress note some random man comes up to me:

Man, "Hi! I am going for a smoke."
Me, "Ok."
Man, "Do you think that it is odd that I am going out for a smoke?"
Me, "Well, I don't know if you smoke."
Man, "Do you think this is funny?"
Me, "No." (me clearly not laughing)
Man, "Oh, you don't get it!"
Me, "I guess not?" (very confused at this point)
Man, "I am so-and-so-in-room-###'s twin brother and thought I'd trick you."

Evidently I did not think that it was as funny as he did since I had never seen the patient in room ### before.