Wait a minute -- Hong Joo said she's never…

Wait a minute -- Hong Joo said she's never managed to change a dream before, but then suddenly she can change the one where Jae Chan was going to fall asleep on the bus and be late to work? Why does she seem not at all surprised that she managed to change what happened in her dream? Also, why does he take the subway to work in an earlier episode but then a bus in this episode? Why were Jae Chan and Woo Tak the only ones who were able to change their dreams? Maybe we'll find out that last one later...but either way, it seems she can change the outcome of her dreams' predictions now too.