Pleased to say my eyesight my has gone back to normal

. Such a relief! Back to work tomorrow.
Saw the specialist for the first time about a week ago and he wants me to slowly reduce my 2 a day dose of Novomix 30 to try and get down to 8 units in the morning before breakfast and 4 before my evening meal. Currently I'm at 13 units in the morning and 8 units in the evening.
I'm still doing lots of reading to try and become an "expert" in this but there's something else niggling me, how can the doctors be sure I'm type 1 and not type 2? From what I've read the symptoms are very similar, if not identical to what I experienced?