Ever bike hard and than your NOT hungry, even though you SHOULD be hungry?

Did a hard 40-mile gravel ride today (wind, hills, crunchy stuff). Sweat and Drank a LOT, but plenty of electrolytes. Had some snacks throughout the ride. I’m not nauseous or sore.

What gives? What am I missing? Usually I want to eat a pizza but not today. Am I burning fat? (Which I have in abundance)