Speculations on Insidious ending?

So I understand the movie, but nobody else seems to have seen what I saw. When the psychic lady Elise I believe speaks to Daulton in the further, a what we think is the demon starts yelling saying," I know who you are, I'll rip you to pieces." In the end, the old hag in Josh's body says the same thing. Does this suggest that the old hag was an even fiercer demon than the red faced one? Was she the one with the insidious plan, using the red face demon the whole time in order to get into Josh's body?