I was going to refrain from commenting on this thread but as you are on insulin I will put in my piece.
The risk with insulin is that you can go dangerously low, so fast acting carbs are sometimes necessary. As
@MrsA2 said, false hypos may be a factor.. As a T1 who is used to insulin, I wouldn't regard 5.2 as too low, but I'd probably take a couple of jelly babies (or equivalent) at 4.2, just because I don't want to go significantly lower.
But I don't know what types of insulin you are on or how used you are to hypos or what your DN has said about the blood glucose levels you should aim for. All these things would influence my comments, which is one of the reasons why forum rules are so strict about not giving medical advice.
Most of the insulin dependent T1s posting will have experienced "eat the fridge" syndrome when hypo (as in you want to eat the contents of the fridge) and had some rebound highs after hypos. Experience helps you mitigate all these factors. (I've just chowed down on the equivalent of 2 jelly babies because my meter said I was 4,4 and dropping and now my meter says 9.5 sigh
).