Continuity mistake: When Derek and Sara kiss each other in the flat of Sara's father, before they start to get naked, the point of view changes from behind Derek to behind Sara a couple of times. In one of the views, Derek's head is leaning to the right as he prepares to kiss Sara (and Sara's head is consequently also leaning to her right), and in the other point of view, is the other way around: both heads are leaning to the left as they approach for the kiss.
Continuity mistake: When Nikki is talking to Derek at Steps, at the end of the first shot, she begins to move her left arm up towards his neck. In the next shot, her left arm is already around his neck, before he pushes her arms down. In the next shot, her left arm is up again as she caresses the back of his neck. In the following shot, her hand has suddenly moved to the side of his head, but in the next shot, her arm is down. (00:29:50)