Untitled Sighting

My Fiancee and I were each in our own cars on Highway M-35 drving home from her parents' house.  We were about 1/2 to 1/3 mile from home, I was driving behind her and on the west side of the highway, just for a brief instance, I thought I saw a shadow of a figure run off to the woods.  I didn't give much thought to it, attributing it to being night time driving and thought it was just my mind playing tricks on me.  A few minutes later after we both got home and situated my Fiancee asked if I saw anything on the side of the road on the way home. She said all she saw was a shadowy figure run into the woods as well, but it was good to know it wasn't just I who was seeing things!  Neither of us could describe what we saw aside from a big, shadowy figure. This was only two days after I had heard a bizarre shrieking noise in my yard.