I take metformin too- you get used to it after a period of time and the side effects go away. I find it's necessary for me to take it with food or I suffer. I take my bedtime dose with Hood low carb milk and I'm fine then too. Isn't it amazing how exercise helps to keep everything in line?
Metformin is supposed to help you regulate the amount of sugar in your blood by slowing down the production of new glucose by your liver. I wonder if you are not eating enough carbs for this to happen? Maybe your brain thinks it's carb deprived and signals your liver to get it some fuel (your brain can only use glucose for energy nothing else)- that might account for your elevated BG counts-
If I skip meals, or don't eat for a long time interval- my BG shoots up- I've tested it over and over again just to be sure. SO I always have my little snacks on schedule or carb up a bit if I know I won't be able to eat on time and it helps to keep me steady and low.
Good luck with your control. sandy