Have I got this right? SPOILER

This is similar in plot to William Golding's book which I won't name to avoid spoiling THAT for folk who have not read it.
Diane is shot and as she dies her whole life: past; present and imagined future, passes before her eyes.
Uma is that imagined future. Uma's character's actions are coloured by the youthful experiences and expectations of the dying teenager who is creating her in her imagination. Uma is shown as purposely odd and so are the other characters Diane builds in her imaginary, dreamlike future. What might seem to be plot-holes and inconistencies in Uma's time are placed there deliberately as a device to show that this is a dream, unconsciously shaped by conflicted Diane's low self-esteem.

When death overcomes the teenager, the film ends.

I thought that it was a remarkable film. It made me sad but, after a while, I realised that this is what a film so closely linked to Columbine and similar tragedies should do. I felt that it was homage rather than exploitation.