Psycho 1960 'shower scene' evaluation

http://www.youtube.com/watch?v=8VP5jEAP3K4
We the audience start out innocently enough watching a woman shred the evidence of her stealing money and ready to right her wrongs. The camera cuts to her getting ready for showering then the water coming out, the audience can only see her washing and hear the sound of the shower but at the same time we are a little creeped out and know that everything isn't as it seems. We then see her from another angle still showering but now she is on the right hand side of the camera so not the centre of attention any more we're almost expecting something to happen. The door in the background opens from behind the shower curtain the audience know nothing good can come of this but are hoping that its the man giving her towels or something, the camera slowly zooms in on the shadow of the person entering the room. The shower curtain is quickly yanked open and suddenly the famous psycho thriller music begins to play. In this moment the camera is focused on the person who has entered the shower, he/she is wearing clothes we've never seen before and we have no idea who it is because they are shrouded by shadow. The camera cuts back to the woman who spins around and screams the camera zooms in on her mouth and the scream lasts about three seconds to add to the sense of horror. The shadowed figure then raises a knife and stabs her, the music intensifies at this moment and there is a pause where we see the woman fighting for the knife with a wound in her arm. She however is injured and cant keep up the fight for long. The killer breaks free and starts stabbing her over and over and over again, the camera cuts from the woman to the killer to the knife as she is repeatedly stabbed. The camera then shows the floor of the bath and we see the blood washing away. The woman then turns trying to run but in the enclosed space she cant escape, we see the same stabbing sequence only from the back now, then it stops and the killer leaves the room, we see her from the back and see woman's hair and a dressing gown we get the impression she is the motel owners mother. Leaning against the bath wall and is breathing heavily and then reaches out with her hand in one last desperate effort to move. The camera then focuses on the hand grabbing the shower curtains, the woman then collapses and we see her lifeless body and the last of her blood wash away the end shot is a slowly closing in on her money wrapped in newspaper the reason she came to the motel in the first place.