Erm, have namechanged because I am worried that I've completely lost my mind...
I often sometimes see things out of the corner of my eye that aren't there - mice scurrying across the floor, beetles etc. I know they aren't there but I always have a second look to make sure.
Other things too, like someone standing behind me and stains on clothes when I'm ironing. I thought this happened to everybody til I vaguely mentioned it to DP who thinks that it is not normal 