Hi and welcome. You are doing exactly the right things and the blood sugar proves the point! I would be delighted with those readings. Although 3.6 is getting into hypo territory, as you are only on Metformin it shouldn't go much if any lower and the liver tends to come to the rescue if you go too low. You may start to be aware of hypo symptoms (feeling spaced-out, sweaty etc) and perhaps have a bit of carb. Yes, supermarkets are full of junk so for us, only a small subset is 'good'. No problem in some potato or rice etc, just keep the daily total down to a level you set yourself.