The Movie Percy Jackson, Symbolism, and Foreshadowing of Future Events

Just to let you know this contains slight spoilers. It was a dumb movie anyway that I decided to watch for it's symbolism. Boy there is a ton. Most of it is just to brainwash kids to think that the gods (fallen ones) are not all bad. They of course use the distorted Greek mythology view in describing the offspring of the gods (nephilim) and that the main character is one of them. So besides the obvious, there are some other hidden messages (perhaps) that I picked up on.

The movie takes place on June 7th (2 weeks before the summer solstice). That is stated in the beginning. Why use that date in the summer when the movie was released in Winter? I don't know. I guess it really doesn't matter that much.

Anyway, towards the beginning of the movie, Percy hears his father (Poseidon) says to him in his head: "Be prepared. Everything is about to change Percy. Everything is about to change". After he 'hears' this he turns around to see his father standing across the street from him. At the same time a bus drives by. In literally one frame of the movie (and it happened so fast I almost missed it) there is a backwards American flag at the end of the bus. Why?

Is "everything about to change" in America?

-There is also 3 locations on a map where they are to find a magical pearl: New Jersey, Tennessee, and Las Vegas. The portal to hell is located in Hollywood (makes sense). Don't know if these locations are foreshadowing anything.

-There was a single storm cloud that expanded over Europe and Asia and heading to the US. It was said to baffle the scientists with savage winds and waves. Just thought I would add this since strange weather seems to be on the rise.

-While in Vegas at a roulette table, the ball (which is this magical pearl) lands on 33. (of course a masonic number)

-Towards the end, when the characters enter Hades, there is a hooded gate keeper there. One of the characters tries to pay him to take them inside (where they are going to save Percy's mother). He hands him over a hundred dollars which is immediately burned in the hooded characters hands. Percy then hands him gold coins which he eagerly takes. This is pretty much saying your paper money is no good. Gold is what is real money.

I know there is more that I cannot remember.