Metaformin and diet

I have recently started a low carb diet and also taking metformin. I am a type 2 diabetec. I recently came off insulin because I felt it was doing me no good as I had put 4 stone on in 9 months and always felt I had no energy. I go running 3 times a week and do 6 miles at a time. My sugar levels are around 16-19 daily and are not coming down can anybody HELP.

Hi I don't eat any bread or pasta. I just have salads and vegetables. I have 2 1000 mg tablets and mainly eat white meat and fish, but my sugar levels stay high. I don't know what I'm doing wrong.