Okay, so, due to a bug I haven't been able to track down, I can't transform into a Vampire Lord.
I go to transform, and my character gets stuck in the transition animation. Tried to look up how to fix, found people with the same problem, but no definitive fix. Woo!
So, I figured I'd bypass the Bloodline Quest all together, used
Setstage 40
Setstage 180
Talked to Serena, had her change me back... boom, problem solved. Go and do the Chalice quest, then after I'm told to talk to Harkon.
I do...and he's in the tutorial room and won't talk to me until after I've completed it... ><
I just need to bypass the tutorial =P