Inquiry about this movie

I get that she's got some serious issues going on, and the whole movie actually makes sense. But there is a few things that are unclear to me:

-When she was floating. Was she imagining that?
-Her face stretch. What was up with that. I didn't understand.

Overall, a very interesting movie. A deep look into mental illness that centers around religion. I think it should've been listed as a suspense thriller instead of horror, tho.