Think I've found a mistake!

Rating: Null/10 (1 June 2004)

MAJOR SPOILERS!!!!
SPOILER ALERT!!!
Ok, I need somebody who has watched this movie more than once to validate this but I think I've found a mistake. And if I'm right, it's HUGE!
The last scene (or rather the first scene) of the film involves Leonard writing on Teddy's photo to "Kill him, he's the one". During the film however, these words do not appear on the photo, only the words "Don't believe his lies".
Now if the end of the movie is actually the beginning, and the previous scenes actually happen AFTER the last scene, why don't the words appear on the photo in the rest of the film? The only possible answer is that the last scene happens directly before the first scene and as far as I'm aware, that's not the way it works.