WHat would you give this response out of 40 in English Language GCSE?

You were meant to be able to tell who was a killer
Mascara traced a line down her cheek, like a writer brushing the nib of his pen against the crimped, thumbed pages of his notebook, each black tear-drop that fell down telling a story of its own. Her opposite cheek tainted the window of the bus black; a gothic windowpane with its black stained glass, cool against her skin. However, this was the warmest thing she was feeling as of now, everything else was overly cold, matching icy pit of rejection in the bottom of her stomach.
The world around her seemed red. Everything down to the rain splattering against the glass-each thump a mocking laugh within itself- to the leftover residue of mud on her shoes. The bits and debris stuck struck her like flesh and bones. It was oddly appalling how an ordinary person, with no interest in the gore of life could be stuck in a situation so horrific. She'd never once thought that such a thing was possible. It was like a movie. And all the characters were oblivious to the lines they were meant to say. They were meant to question her, like it says on the script, they were meant to be shocked and call the police. But the characters stayed unknowing.
A small scream of a child filled the air and suddenly she was out of her own mind, away from everything she called home. Her bloody hands around the hammer. The sickening crunch of metal against skull. Her own surprise and shock at what she'd done. But mostly...mostly of the admiration that she had the nerve within her to carry out such a deed. The admiration of the fact that she was here now. She was this far.
A hand laid itself on her shoulder, bodiless, nails painted a peculiar blue that she'd only seen on a person who was meant to be dead. She was back for revenge. She was going to drag her from this bus and kill her. She was going to break her skull to pieces and then keep her hidden in some forest like she'd done to her. She wanted to scream out but the very feeling of ice settled into her lungs and all she had to do now was think about breathing but what was even the point when it would be taken away from her so quickly?
"Dear? This is the last stop." stammered a frail old lady. She turned her head and saw that the hand ,indeed, did have a body. And the nails were firmly white, hands riddled with veins.
"Oh yes thank you." she whispered, standing up and walking off the bus before the lady could say anything else. Did she not know she was talking to a killer? Could she not hear the huskiness that told her she was a murderer? Was it that every other person around these days could be a criminal and us ordinary humans could simply not hear so?
She hopped off the bus, the sound of her shoes hitting the tarmac of the sidewalk like a drum beating to match that of her heart. And it occurred to her to keep up that rhythm or else if she didn't her heart would stop beating as well. So, she ran, ran faster than her life could say, lights flashing around her like fluorescent laser, beaming into her sight and then blinding her. She had to stop or else she'd surely keep living.
She stilled, looking around her. She was in front of a church. How ironic. That after she'd committed one of the most contemptible crimes known to mankind, she'd end up in front of the one place that warned against it. The kind mediating face of Jesus peered down at her, a face promising forgiveness yet in those white eyes she saw the acknowledgement.
Yes, this was a face of a murderer.