Is she being tsundere or is she actually mad (judging by her 💢)?

she's a suicidal pessimistic regressing into tsundere. despite claiming everything is pointless she still clings onto various things that are arguably just as pointless like teddy bears. despite claiming bodies are mere flesh and even making multiple attempt at killing herself, the moment she caught a cold and then got taken care of by sensei she gets flustered and complain about it but follows along anyway.

I think what cemented her canonical tsundere status was her valentine event story.

ACVI elements: The hermit crab from G6 Red's emblem walking on the sand, Schneider logo on Sensei's shirt, Elcano logo on Sensei's pants and an unknown AC (Is it from Alea Iacta Est ending?).
Additionally, ドヒャア is an onomatopoeia often associated with Quick Boosting in AC series.