When Ryan is pouring Dawn a glass of champagne, the foam appears to be filling half the glass. When he hands her the glass, it has instantly dissipated. When he pours his own glass, it takes much longer for the foam to dissipate.
Dawn O'Keefe has brown eyes as a child in the first scene, but has blue eyes in the rest of the movie. However, 10 - 15% of Caucasian people experience some eye color change. It is not unlikely for a child's eye color to change from brown to blue.
When Dawn is 'checked' at the clinic, she flees the room screaming after 'biting' off the gynecologist's fingers. As she opens the door she's displaying very visible underwear lines through her surgical gown. Given the antics displayed, she's not supposed to be wearing any underwear.