Many thanks for all your comments. They are all useful. I had a feeling it was coming for about 18 months. Had an emergency appendectomy last february and I've not 'felt like me' since. I think my pancreas has been doing it's job only partially.
On my left leg I have a bruise/ulcer about 2 inches across. I've had it for months. When I saw the doctor 3 months ago, she dismissed it, said do nothing to it and it will go away. I now know this is an external indicator.
In answer to the question, yes I am on that drug, 500mg to begin with, once a day. After 2 weeks, up to 2. Then after another 2 weeks, up to 3. Not had any side effects yet apart from a bit of a fuzzy head!
Evidently there are Diabetes educators attached to the local PCT, who you can evidently get advice from. So, I am going to try and contact them. But I know that the best thing to do is talk to the people who have to live with it.