I experience this too. Also I've noticed that before it happens I get this kind of disconnected feeling, like I'm standing next to myself (I know it's weird!) and then after I see it, it's like I'm back standing within myself but I get this really heavy sensation like the gravity on earth is suddenly a bit stronger. It seems like moving takes a bit more effort than before the whole thing started and I catch myself for several hours afterwards, just standing somewhere realizing that I've been staring into space for who knows how long.
Once I started to believe that I was being abducted by aliens but now I don't know why this happens, no one seems to.
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I = Vegan!
Animals = Friends.