That was a gripping story, and you have entered very well into the mind of a serial killer (gulp!!). Your story has an excellent chance of success in this contest as you gripped the reader's interest from start to finish. Sending best wishes.
Spelling: "wither away " not "whither", and "lying" not "laying"
Well! You have certainly succeeded in crafting a great horror story, that didn't move out of tone by a single step. I am particularly impressed that you managed to do it whilst writing in the first person. I have always understood that to be difficult, and particulaly for the horror/terror/thriller/mystery genres it is reputed as being hard to sustain the mood. You did it. Well done.