MOST RECENT PARANORMAL EXPERIENCE - GHOST SHADOW?

I constantly have the sense that someone is standing directly behind me when I am in the kitchen of my apartment.  This time though I received proof - a shadow of a man was cast on the wall in front of me just as if someone were indeed standing behind me.  I looked behind me and nothing was there then turned around and the shadow was still there.  I repeated this several times before leaving the room and shutting off the light.