I test when I wake up in the AM and a few hours after eating dinner.
You probably have DP (dawn phenomenon) Your liver is helping you to get going in the morning by providing energy in the form of glucose. Every ones liver does this. The problem is your body cant handle all that glucose so your BG goes up. Metformin helps to reduce the liver output of glucose, Metformin also increases insulin sensitivity.
When do you test "after eating" ( 1 hour or 2 hours...)?