The clock on my computer went back an hour, and I didn't even realize. I remember Windows doing a whole song and dance about the time changing and notifying you as it did it. Don't remember it ever just happening while I was still on the computer. Hmmm..... So it is 2:30, not 1:30 (well, it IS, but you know what I mean) so there's a reason I'm an hour sleepier than I thought I should be.
and if you understood that, be afraid!
Later: oh, yeah, I never did say what it was a sign of. Well, you can make up your own theories!