Metformin interferes with the ability of the liver to release glucose, so an increase in levels first thing in the morning might simply indicate that you are getting back to normal, whatever your normal is.
I could not live with Metformin, so just stopped taking it, and stuck with eating low carb. I did not really expect to be in the normal range in a few months but that proved to be the case. If I had still been in the diabetic range I would have eaten fewer carbs rather than go back to taking the tablets, but as it turned out, all was well. My after meal levels are under 7mmol/l most days - if you are not seeing spikes that is the main worry dealt with.