Y'know I think one of the biggest clues that Stephenie Meyer just writes whatever with zero forethought into how that should play into the universe she's creating, is the blood typing scene. I'm sure I've seen someone talk about this before, but having Bella be able to smell blood (even the small drop on a students finger when they also get brought into the nurses office) and having it effect her so much that she can't even be in the same room and then to not make that like a major part of the plot in a vampire series is so stupid. It's set up so it could be like Bella had a tiny bit of vampire DNA in her from one mating with a human centuries back and she's part of that lineage, especially with Breaking Dawn and now knowing that's possible. It would explain why she takes to vampirism so naturally, she's been dealing with a level blood sensitivity her entire life so she's able to control the blood lust much better than any normal newborn, and it could even be used to explain why her blood to everyone smells so incredibly sweet as a human. Yes she's Edwards singer specifically, but in almost each book a comment by a different vampire is made about how good she smells. There was just so much potential for that blood typing scene to lead to something greater but it was left as just a throwaway thing to make Bella seem even less like other girls to have Edward be interested. I remember the first time I read the books and got to that scene and I was so excited cause "omg is bella not totally human? Where is this gonna lead?!" And then it lead nowhere. It could have all come together in BD with the gathering of witnesses and an old friend of Carlisles comes and recognizes the last name and that bella maybe resembles the girl that vampire mated with in some way.
Anyway Stephenie really said it herself when she said she "considers nothing"