(SPOILERS) Bioshock Infinite questions

Does Burial at Sea Part 2 take place in the same demention as Bioshock 1? There are continuity issues if they are. We don't see any Bioshock 1 plasmids, only renamed vigors. Eve is dranken, not injected. And I'm pretty sure there was a voice recording in BioShock 1 from a civilian explaining how creepy the big daddy's and little sisters are together. Which would mean that they bonded before the civil war, but Elizabeth bonded the first big daddy to little sister 2 weeks after the revolution began. Is it that Elizabeth's actions happened over more or all raptures? And the one we play in BioShock 1 is a parallel universe where the only tears made were Booker (Ryan) and Elizabeth arriving from other dementions?

If Elizabeth took it upon herself to kill all comstocks, why didn't she kill the Ryans too? Was Ryan at one point a Comstock? Or is he just a Booker who changed his name and chose a completely separate path than the other two?

I'm sorry, I have a lot of questions. Just finished the games after a fantastic long binge and the explanation still left me with many questions