This photo definitely has shadows so first and foremost I comment you for meeting the challenge. I really like the lit window in the darkest recesses of the building. The lighting on the back wall of bricks is very nice...lots of detail yet very dark and mysterious...shadowy (is that a word?). Unfortunately your shadow doesn't really look "human." In fact, I was wondering what it was that was casting the shadow but didn't think it was a person until I read your details. I think the shadow of yourself lacks something... A suggestion would be to perhaps reveal an arm or a more of a profile so we can clearly tell it is a person. Better still if your photo can tell a story somehow. Does the shadow have a knife in it's hand? Is it reaching for something? As it is, the shadow is just sort of there doing nothing and doesn't lead me to wonder too much about it. Another interesting idea is to have an actual person squatting in the darkest shadows of the recessed area where you can just barely make out their face as if they are waiting for someone to pass by as their next victim. That scene with that lighting and a person hidden away in the dark shadows could be really powerful. Again, nice job on the lighting...work on telling a story.
What a scary picture. Would the rules have allowed the white spots on the walls to be cloned away? I think they are distracting to the mood of the picture otherwise well done.