I worked in the university library and a few times a year we had girls studying for hours on empty stomachs (brains consuming glucose is a different process from normal). They usually felt dizzy, were bleak and confused and were sometimes sweating and usually came to ask for some OTC painkiller or something. Usually gave them some of my dextrose tablets and someone's lunch and almost always it was fine a few minutes later. I'm pretty sure they had hypoglycemia. Though for (us) diabetics hypoglycemia where we start feeling it isn a considerably lower blood glucose level than for most regular people so there is some difference in how far you are gone down the rabbit hole already.

This necessity of eating after you overate but mis-treated is one of the worst feelings in T1. You know you screwed up and you know you're going to pay for it, because you'll probably spike later and you don't know if it is the big meal you just ate or the snack you ate to keep from going low first. I love pizza, my body hates pizza