Continuity mistake: When John and Emily start their tour, the guide asks them where they're from. After that, they start to walk towards one hallway. John and Emily are in the back. The next shot, they're in the front of the pack. There would not have been enough time for this to happen.
Continuity mistake: Towards the end of the movie when John is talking to the President after he got shot in the watch, John has a wound on his right arm. A few minutes later when John is outside the White House you can see his wound is different, it's bigger and there's lots more blood.