So much wrong with this movie

Amy is a waitress and a minor, yet they make her work until one in the morning?

Amy gets hit by a car driven by Madison and it looks more like she got a rash.

Madison gets handcuffed with her hands to the front, making it easy to kill those cops.

What went on between Madison and her old boyfriend is never explained. We're to assume that Madison took off her boyfriend's seatbelt and caused him to crash, yet no scratch on her?

I love that when Madison and Ben get dinner together, they don't eat a thing out of those burgers and fries, yet Ben says he should take Madison home with no bite. What a waste of food!

I thought Ben's teammate died because Madison sliced his head with a scalpel because of the way he was bleeding in the water like that. But from a baseball bat, you could get a bleeding wound like that?

If Madison really wanted to kill Amy, she shouldn't have told Ben where they were. Obviously Ben is a good swimmer and would come up with some way to get Amy out.

Finally, when Madison pushes Amy into the water in the wheelchair, she immediately becomes unconscious just from hitting the water? Doesn't even make a struggle to get out of the chair herself?