So right when I enter Fort Dawnguard, everyone from the new recruit to the lackies to the leader attack me. (Sorry i don't know their names, thats how far i've been able to play) I can also suddenly feed on people even though I have never, ever been a vampire. I bought this $20 game and I can't even start to play it. Why do people like me have to be guinnea pigs for supposedly completed content? I realize there will always be some sort of bug in games, but this is gamebreaking.

did you enter past level 10?
did you have a bounty in the Riften area?

try reloading to before you ever entered the dawnguards cavern. Go to Riften and talk to a guard to make sure you have no fines. go in and out of a few places to force the game to change cells a few times.

then go back and check the dawnguard, that fixed the problem for me during the beta, it turns out I had a bounty and didn't realize it.

ill try it, thanks

I cleared my Riften bounty and changed cells a couple of times. WORKED WONDERS. Everything seems fine now, thanks!