I've made some stupid mistakes and I'm very annoyed with myself.
Stupid mistake number 1: I cast on too few stitches for the front of my Notre Dame de Grace jumper. I only noticed my mistake when I held the front up against the back to check I was starting the armholes in the right place. Grrr.
Stupid mistake number two: I made my Clapotis too wide and have run out of yarn before the end. I'll have to frog it completely and make it narrower because there is no more of the yarn. Grrr again.
And what's more, I think I've got a knitting-related pain in my upper arm. So I cast on a very simple sock to make me feel better. So far it seems to be working.