I'm in a similar situation, although I'm 2 and half months in, have good blood pressure and slightly lower BG readings. When I was first diagnosed my GP said he would start me on 2x500mg Metformin and then probably double it later on.
The trouble is, by low-carbing I got my BG in the 5-7mmol/L range relatively easily but with a very restrictive diet (<<30g of carbs per day).
NHS practitioners seem to think that anything less that 10mmol/L is a "good" score, so that I doubt that he will now increase my dose. I booked an appointment last week and told him that I'd like to increase, because I'd like a bit more latitude with my carb intake, and because I'd like slightly lower scores.
To his credit, he is sending me for a Hb1Ac test and will decide whether or not to increase my dose after that. But I'm guessing that my Hb1Ac will be good, and that he won't increase my dose, leaving me stuck as an ultra low-carber.
Even after 2 and a half months I still get false hypo headaches when my BG < 5.5 mmol/L.
I'll let you know how I get on...