It's a bad thing not because it's finite: your body makes hormones when it deems necessary. The issue is when you regularly have high levels of those hormones, it will cause effects like weight gain, fatigue and skin issues, to name a few.

Your heightened sense is a temporary mode at the cost of other functions of your body. Going back to your analogy, hormones influence things like a bunch of presets on your motherboard. Your body cranked up the CPU because you didn't have enough sleep, but this will cost you in other areas like your immune system.

Unlike a computer, we can't simply draw more energy from the wall to crank up the settings permanently. So these hormones/presets helps your body focus on what you need the most at that point, redistributing your available energy.