big agree! plus i love the author's phrasing of the face warming rather than blushing, bc we all can feel the physical face warm even if some skin colors can't actually show that in a blush
honestly, i'm pale as hell but my cheeks are naturally really red because i struggle with body temperature regulation and i have pink undertones anyways, so its not super visible when i blush. the way i can physically feel my face warming is the worst part because then it distracts me, i get embarrassed about it and that gets me more flustered, and then anyone i'm talking to can notice as easily as if i was visibly blushing LOL. especially since i've had to literally fan my face before because it got so hot LOL
but yeah, def agree, body language being written is always so fascinating (and hard LOL). i default less to blushing and more to stuff like being unable to stop a grin or fidgeting in place while being unable to make eye contact.