Bobby cuts his finger when he inspects the hole in his wall and washes it in his bathroom sink. When he looks at the prescription medicine in the cabinet, the injury is suddenly gone in the closeup of his hand.
The grease stains on Bobby's face in the car workshop change between shots.
The position of the dress fabric on Alyssa's mannequin changes between shots.
Alyssa sees Gina knocking on Bobby's door and immediately suspects he's seeing another girl and tells her friends about this. The fact that Gina was covered in bruises and was obviously in tears did not seem to occur to her at all.