I really enjoyed your story. You were going for a realism angle and I think you succeeded for the most part. The ending seemed a little rushed and a little more detail wouldn't have hurt, but overall I think this is above average as far as fan fiction goes.
Also the intro was pretty cool too. Very unique. It would be cool to have a little more background too, but at the same time I can see how you're kind of trying to leave it open. Overall, good job. ;D