fear of scarcity

I've been sick the last few days.  Just a head cold or something, but blowing my nose this much is debilitating in itself, and feeling rather lousy on top of that.  Being sick feels a lot like how I normally feel, only amplified.  It's even more difficult to concentrate, or even think about doing anything.  I hope this is my last day of it, because I have another paper to write. 

That I might have to do it while feeling like this seems particularly unfair, but I guess it's the same old idea, might have to do it anyhow.  Get over this inertia, hammer something out.  BJJ is out of the question though.  This would not put me on good terms with my training partners.

I keep wondering about this feeling, most noticeable when it fluctuates.  What does it mean to feel like I don't have the energy?  I can't?  If my apartment were suddenly besieged by hornets or something, I'd find the energy pretty easily.  Not because of any miraculous burst of adrenaline, but because physiologically, the energy is there.  I'd just have to collapse into a heap and take a nap shortly there afterwards.

On an unconscious level, I'm calculating how much energy I have, and trying to keep the needle from dropping into the red.  Not actually being on empty, this becomes arbitrary.  Subjective.  How do we figure how low is low?  A quarter, a third, below half?  Half of what?  Is this based on some lizard brain instinct to make sure we always have enough in reserve, for those times when we might go a few days without food?  Do mental health conditions throw the whole calculation off?

I'm pretty sure that I have more energy than my lizard brain is telling me that I have, even when I am sick.  My immune system might need that, though.  Think I read somewhere that healthy fats are best for keeping the immune system powered. As long as I eat some peanut butter or something, I should be able to write a paper without all these unpleasant biochemical reactions hassling me like this.