Hello Jakki and welcome. What do you mean by a hypo? are you only on metformin for your diabetes, or do you take nay other diabetes meds?
Our bodies get used to a high level for blood sugar, and when it lowers, in type 2's, it can make us feel shaky and dizzy or weak for a short while. If we rest, our liver will compensate in a short while without need for any sugar from us. Its not like the life threatening type 1 hypos, but can fell scary the first time. I suspect your low carbing is working and so your body panicked as it wasnt getting its usual levels of blood sugar. Our bodies get used to it on a week or two. In the mean times, just stop and breathe for a few mins if it happens again, all will be ok and they we happen less and less as your body gets used to the new diet.
Its different if you are on med which can cause hypo's in type 2's but metformin isnt one of them.