(at around 48 minutes) When Cassie is making tea, a kettle is heard whistling but when she picks the kettle up it is an ordinary kettle not a whistling kettle.
The movie starts with a close up on Martha Tinsdale's feet: she is wearing solid black Mary Janes. She opens a gate, enters the good witch's property and as she walks away from the camera we clearly see that she is now wearing leopard print pumps. We see Martha's shoes three times in the opening minutes, and all three times she is wearing solid black Mary Janes.