I liked it, mainly because of the mystery voice. The rest of the story was the usual opening of an amnesiac finding himself at a crime scene, but the voice gives it a touch of eerie charm. I hope it isn't just the voice of his conscience because that would dull it all down a bit.
As for your writing skills, you can pace a short story well enough and you almost know how to punctuate dialogue, which means you're on a good level. As a rule, your dialogue tags should always be in lowercase, even after following an exclamation or question mark inside quotations. Typos aside, it was a good piece. Maybe not as self-contained as should be expected by a short story, but not bad.