I genuinely appreciate your concern. I just signed on to throw an edit... I fast often enough that I was fairly certain this wasn't related, but just laid low long enough to verify. I also get migraines often enough that it reinforced my hunch that it was indeed that - and not a blood sugar thing.
Sure enough - I powered through, and thankfully feeling much better. It's weird. I'm still not hungry... And despite the tiny lingering "after-headache" I feel amazing... the way I normally feel during fasting. SO yay! still no calories... and feeling amazing.
But seriously - I am very thankful for your concern and nudge to do the right thing. I should have known better than to post whilst delirious in migraineland.