Have you ever experienced recalling your dreams and think "Wait...wasn't that the night before?" This usually happens to me when I'm recalling one dream, and I go "Oh, yeah, I had another dream earlier on" and then I think "Wait a second...wasn't that a few nights ago?"

I suppose you'd only experience this if you did not keep a dream journal at the time (since you can just look back at it). I have a pretty good dream recall without a journal, so I can remember my dreams for days with little loss. Many times I've been recalling a dream after I wake up and have to actually sit there and think whether that was last night, or the night before.