Don't let anybody say if you don't 'get' this movie you're stupid
You're not meant to 'get' this film. You're meant to feel it. There is no 'explanation' to this movie. And if you thought it was pretentious garbage then that doesn't mean you're dumb.
Total self promotion here, but I wrote a thing about how the movie's meant to be felt not thought about here: http://undertheunderlook.blogspot.com.au/2014/07/only-god-forgives-frequently-asked.html