Your brain doesn't receive serotonin, dopamine, and norepinephrine. It builds them — out of magnesium, B6, B12, and folate.
Sustained stress burns through those exact raw materials faster than food replaces them.
So your brain starts rationing what's left.
The basics stay intact. What goes first is the higher-order output: focus that holds through a long afternoon, steadiness under pressure, energy that doesn't need a third coffee.
It was never three separate problems. It's one supply, draining faster than it refills.
You're not weak. You're spending faster than you're restocking.