Maximum PC

I just got the new Dawnguard DLC (PC Version) for Skyrim yesterday and I finished in the Cairn and after I get the Elder Scroll (Blood) I leave the Cairn and then I have no new objectives and can't figure out what to do. I watched the walkthrough on youtube and it appears I should talk to the Moth priest but when I go to talk to him he just says the same stupid thing over and over again and I have no dialog choices. Please help I have been really enjoying Dawnguard and am really not enjoying this issue. I love it so much that since I bought it yesterday I have played 15 hours of it. Thanks in advance!

Figured out the issue! I hadn't gotten the first Elder Scroll yet so it would not let me continue after I received the first Elder Scroll it started the mission. Hope this helped anyone else with this issue!