A childhood belief about sleeping

I had a dream that i was in my primary skool and these flying tin cans with legs and arms and faces where trying to get me. they were called german measles. For years after that i cudnt sleep with my back to the room coz i beleived that the german measles were goin to get me. I was always saying to my bro "look theres german measles behind you!" I really beleived they were real. But not anymore.thank god for that