I've had that shaky, irritable, sweaty, confused, relieved-by-sugar feeling most of my life. I used to be a student nurse so could measure my BG on the ward. It would regularly drop to below 3 mmol/l and on one occasion it was 1.3 (although I'm sure this must have been a fault with the machine). I found a sugary snack would have me feeling better quite rapidly, but sometimes within hours I would be feeling like rubbish again. For various reasons, my diet was pretty terrible at that period of my life.
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