In my experience all hypos are different, sometimes how low you are doesnt reflect the symptoms you feel, ive been as low as 1.6 and literally had hardly any symptoms and didnt expect it to be that low, ive also had hypos in the high 2s or low 3s and felt like i was about to die. In my experience its when you've had a long exhausting day and are tired that you will not experience many symptoms while hypo, i think youre body is depleted of adrenaline or if you have had a hectic day been exposed to alot of adranaline and it doesnt effect you as much. The night time ones are the worst as you can be low for a long time and not realise, and the adrenaline can build up, then its like BOOM, you wake up, and are twitching, sweating, confused, heart pounding, then run downstairs to the fridge and downing anything with sugar in it.