Hi
@gary 196, An interesting question. Based on my experience as a diabetic and nor as professional advice or opinion.:
3.5. mmol/l is defined as hypoglycaemia (see Home page - Blood sugar levels).
Driving at hypoglycaemic levels is considered dangerous. You are prescribed glicazide which is an oral hypoglycaemic agent and your GP is supposed to provide you with a certificate or filled out form (I can only speak for Australia where i live) to say that you are diabetic and fit to drive, provided your BSL is above 5 mmol/l.
My concern for you is that if you attempt to drive at a BSL of 3.5 mmol/l you could have an accident which harms you, someone else, or their pet or causes damage to cars, property etc. Ask a lawyer how much you gain to lose financially and personally.
You should listen to your nurse. Too low is bad as she has inferred. Be wise, see your GP, sort out your carbs and BSL with your nurse, be a good boy and get your license sorted.