Erin, I was bent over picking something off the floor. I grabbed it, and straightened up, and on the up smacked my head on the frame (bottom) of the painting.
The painting juts out from the wall a bit (it's box-like, hard to describe, but imagine about a 2x2 width board that runs all the way around the painting to form the frame), so the painting isn't flush to the wall and therefore coming up from bending down (as I was right against the wall behind the couch that I had moved out at 1 end) I smacked the left side of the top of my head along the middle bottom of this painting.
No bump today, no tenderness, but I will mention it to the doctor when I see her again. In the meantime, I'll keep it in the back of my mind that I did that (smacked my head) just in case anything odd comes up otherwise.
Today's walking day.... about to head back out in fact, was out for a bit already.

Thanks for your concern ladies!