I'll probably be commenting again, but just this for now: James emerged from Voldemort's wand before Lily did. They were supposed to come out in reverse order of their deaths. Did James really die after Lily did?

That was an editor's error in the first printing. It was supposed to be Lily, James. The editor said it was wrong, JK said Oh, OK, and didn't check herself. It's been fixed in later editions.