Continuity mistake: In the beginning of the movie, Rachel lies down in the shade of a billboard on the side of the road. When they cut to the wide shot the shadow of the billboard is on the opposite side so Rachel is in sunlight. This might have symbolized the passing of time, but in the next shot, when Harlen comes to wake her, she is in the shade again.
Continuity mistake: When Rachel visits Georgia for the first time, she has rather worn off reddish nail polish. When she wakes up in the morning on the couch, obviously zoned out because of all the walking, without time to do much about her appearance, she has a professional looking French manicure. In the next scene she has red nail polish again.