Visible crew/equipment: When the shelf falls in the store, you can see the rope attached to the top of the shelving unit being pulled from off-screen triggering the collapse of the shelving unit, it was not the girl's weight that made it tip.
Other mistake: Carol grabs a pot holder with her right hand and removes a small cake from the oven. The cake pan is obviously not hot. It starts to tip and Carol steadies it by placing her bare left hand on the underside of the pan.
Continuity mistake: The bottles of pop on the kitchen table keep changing position from shot to shot. (00:22:55)
Answer: The dangling bracelet was used for dramatic purposes - to keep the audience on edge.