At your age, did your doctor actually make sure you are not a T1 diabetic, or did he just assume T2.
What were the circumstances of the diagnosis? Did symptoms come on slowly or rapidly? Are you gaining or losing weight?
Give us this information, and we'll be able to point you in the right direction, or at least explain things.
Metformin is a good medicine, but "diastix", are these for dipping urine? :?
If so what you need is a blood sugar meter. Dipping urine won't tell you how high your blood glucose is, just how much glucose has spilled over your renal threshold since you last emptied your bladder. that's not actually much help. It is, however, cheap. The best use of Urine sticks is to identify which food or drink you might be about to ingest, that might have glucose in it. you dip the food.
In any case if you don't change your eating habits, Metformin alone won't get you down into the safe zone, which is below 7mmol/l in blood :? .
Read the threads on success stories and low carb eating. If you don't know what a carb is,read my carbohydrate 101 post.