Why does hunger sometimes manifest differently (fatigue vs. anger vs. sadness)?

In the past, sometimes I'd just get brainfogged and tired and have no motivated from hunger. Other times, I feel perfectly energetic despite having not eaten at all, and I would feel hungry, but I'd have some unexplainable amount of anger or sadness that was tied to that.

It just seems like every time I don't eat for a long time, I'm spinning the wheel on how that manifests. Why is that? Why isn't there a consistent "you're hungry" feeling?