Total Lovecraft Moment

I just had what I can only describe as a total Lovecraft moment. I was lying down and had been looking out the window, kinda dozing, and then suddenly just got like bodyslammed by a wave of existential horror. I sort of jerked up and then it was gone. It wasn't like a nightmare since I wasn't really asleep, I can't even remember if my eyes were closed or not. But it was this total "everything is horrible" moment that just made me feel kinda sick and weird. Has anyone ever experienced anything like this? Or is this just what happens when you watch three hours of The Decalogue and have PMS??