Really, this whole movie is a giant slip up that never should've been made. But whatever.

When Smith first meets the red-haired girl at the party, she pukes all over his right shoe. There are at least 2 shots of his puke-covered shoe, clearly showing it as his right foot. He then goes to the bathroom & begins washing his left shoe in the sink. He's sitting on the counter, with his left foot in the sink cleaning his shoe. And no, I'm not looking at the reflection in the mirror, which is also visible.