Yes, but only if you follow the correct dialogue lines.
Were you infected with Sanguinare Vampiris? You may have became a vampire without realizing. If this is a glitch then you could try asking Serana to make you into a vampire, then talk to the dawnguards. They will give you a quest to cure your Vampirism and you should be fine after that. If you can't become a Vampire from Serana skip to the second step and talk to the Dawnguard.
No, she is an essential character and so can't be given to the Blades.
press the d-pad
Skyrim Dawnguard adds the characters Serana and Velerica both who are Daughters of Coldharbour, which means they are pure blood vampires who had there powers given to them by the Daedric prince Molag Bal. Molag Bal is also known as the Daedric Prince of Domination, vampirism, corruption, slavery, and RAPE. If you speak to Serana about becoming a pure blood vampire she'll tell you it involved a degrading ritual were the women offered themselves to Molag Bal, which means Molag Bal raped Serana and Velerica.
Last time i saw her i was fighting giants outside of Whiterun and she got threw into the air and i haven't seen her since. Help?!
You can marry any NPC character in Skyrim through the use of console commands. With the exception of Serana from the Dawnguard DLC (There might be a way to marry her, but I haven't found it). Vivienne is not a character who can be married without console commands.
Alberto Serana has written: 'Improvvisi'
Skyrim for Pimps - 2011 Huge Vampire Wang - 3.2 was released on: USA: 4 August 2012
there is no posion that will turn you into a vampire but a vampire blood can turn you into a vampire
Skyrim for Pimps - 2011 Huge Vampire Wang 3-2 was released on: USA: 4 August 2012
Get beat up by some vampires
There are 13 perks in total.