I have heard stories about some bugs that happen when you're a Vampire. A lot regarding the face. I heard that you can't use the face changer, which svcks for Vampire users, but I plan to cure myself of Vampirism to go back to my werewolf power. I know how to do it and all but I noticed some changes to my character's face when I am a vampire, such as the cheekbone rising. If I cure my vampirism, will my face go back to normal as it was before becoming a vampire, or will I still have the same face now? Now really fond of vampirism changing my bone structure, but it was the only way to...

If I were you, assuming you don't want to stay a Vampire as you said, I'd load a previous save and choose the soul trap option to enter the Cairn. It's the smarter choice as you can simply get your soul back soon after.