As I age, I've learned to distinguish "not being excited" (languor) and "being tired" (exhaustion), which to my younger self felt like the same thing. The former is not always caused by a lack of energy, but also excessive idleness, especially if I'm doing things that requires attention but also isn't intellectually stimulating. When the author refers to "normal tired" and "dead tired", I think that echoes with my tw…
I wish lack of excitement and being tired felt the way you describe, but if anything it's the opposite.
I get more dopamine from being exhausted physically but overextending myself than I do from being bored, much to my misery.