Olympics Headaches

I woke up Sunday and Monday mornings with headaches and finally figured out why.

When I woke Sunday, I felt sure the barometer must have dropped.  This diet has kept headaches at bay so well; why would I have one on a weekend morning?

Then this morning, I woke up with an even worse headache.

And then it hit me:  both nights I had failed to go to bed at the same time as usual, and both mornings I woke up many hours after normal.

That going to bed and rising at the same time trigger really affects me.  I need to remember it before I stay up later, even if it's to watch the Olympics.