Continuity mistake: Towards the end of the movie when Dr. Giggles house blows up, Jennifer and her boyfriend fall to the ground twice.
Continuity mistake: When Jennifer is wheeled into the operating room, the nurse finds blood on the floor and discovers two bodies. Later, after the doctor has killed Jennifer's surgeon, she runs out of the same door, but there's no blood. (01:20:00 - 01:23:00)