I did it, if someone has the same problem, go to Dalaran and find Panda Monk next to flight master who will send you do your Class Hall. Then just complete the quest, and do Mistweaver monk's campaign ...
I did 6 stages, everything was fine. Then I came to the Master Fel Stone and clicked on it, cause it has to open that Demon Portal. It attacked me, I killed it.. I don't know if I should've don ...