Had a close call at the weekend......

and i was only spectating. Late on in the day i moved to watch at a different spot. Was watching the bikes coming out of a corner about 20 meters from me on my left and going past about 4 meters in front of me. I was leaning against my arms which were on top of a wooden rail on top of the fence so was bent forward a tiny bit. After 10 minutes or so i straightened myself up as my arms were getting sore with leaning on them and turned around to my right a tiny bit and was now leaning on the fence with my left elbow which now had me standing at my normal height about 25 mm higher than leaning on my arms.I was now watching the bikes going up the straight going in to the next corner. About 60 seconds after turning around i got hit on the side of my head just above my ear from a flying stone from a passing bike. Yes i have been in more pain but i really felt it and my head was still throbbing for over a hour after it hit me. The reason i am posting this thread was that the stone hit me on the left hand side of my head so the stone had to be throwing out of the front of the bike at a angle as the bike was going up the straight behind me. Something which you would have thought was near impossible to happen. Anybody else ever heard of this happening before? I have no doubt in my mind that if i had not turned around 60 seconds before it would have hit me in my left eye..Kind of shaken me up a bit thinking about it!