When I first read this, I thought you had somehow added molasses to your meal plan and it was blocking you.
Now that I realize that is not the case, I say - take the nap. I sometimes take a nap and wake up at 5 and I survive. I am usually still tired enough to get to bed at a normal time.
or go for a power walk with big arm swings to get some energy. (but I'd probably nap.)