Hi Lottie and welcome to the forum
That's a really bad time you've been having!
None of us are doctors so can't really offer proper professional advice but my own totally unprofessional opinion is you are most likely T2 or maybe in the initial stages of LADA. I would doubt you are T1 because if you are only getting readings between 9 and 13 it would imply you are at least producing some insulin. Whether those high readings are being caused by a lack of insulin which would indicate LADA or by insulin resistance which would indicate T2 is what I though a GAD test along with a c-peptide test should have determined. I think a c-peptide test measures how much insulin is being produced. It is the primary test used to determine T1 as T1 diabetics produce no insulin.
What many members have found regardless of what Type of diabetes they have then carbohydrate reduction is a very good way of reducing levels. I am plain vanilla Type 2 so I can only tell you what I did to get my levels under control. There are many T1's and LADA members who do a similar dietary regime to myself.
Another thing that maybe of interest is that very low carbohydrate diets have been found to be beneficial for epilepsy sufferers. Again I can only point you at some research obviously I am no expert in saying if it would be suitable for yourself.
Anyway I was diagnosed in December last year and using the advice I found on the people on the forum I got my blood sugar levels back to normal within around a couple of months or so and I have also normalised my cholesterol levels and blood pressure as well. I have now lost over 3 stone in weight too. My doctor is very pleased how I am getting on and has advised me to keep doing what I have been doing since it's obviously working really well. Not a cure as I still have to be very careful what I eat but I feel loads better than I did.
Diet wise its really easy. Just drastically cut down or better cut out all things with plain sugar, so biscuits, cakes, sugar in tea and coffee, pure fruit juices, non diet versions of soft drinks. Next and
really importantly try halving starchy foods like rice, pasta, potatoes, bread, cereals and any other flour based products. Replace what's now missing with extra meat, fish, eggs, cheese and especially vegetables. Vegetables that grow above ground are best although most of us find carrots fine. Things like yoghurt are fine as is a small amount of fresh fruit. I find the ones that end in "berry" are the best. If you don't mind artificial sweeteners things like Diet Coke are fine to drink. On the starchy foods that are left swap try brown basmati rice instead of white and brown or tri-colour pasta. The bread that most recommend is actually Bergen soya bread but some do ok with wholemeal as well.
The above diet is close to one you would be one recommended to try by the Swedish Health service. It was introduced in that country last year and the American health service and several other countries health services recommend something very similar for Type 2 diabetics. In the UK the diet guidelines are now over 30 years old and are only gradually being updated. As the UK is lagging behind you have already seen what I and other forum members recommend is different to what your are told is a good diet for you follow.
Obviously you have a meter and strips from when you were on insulin. Are they still prescribing you strips now you are just on Metformin. If so you are one of the lucky ones so keep in the docs good books!
As you are probably aware the reason testing is important is you should try and keep your blood sugars below 8ish two hours after eating any meal. Above the 8 value is where the dangers of complications do begin to occur according to diabetic experts. The problem is every diabetic is different so my earlier advice to halve starchy foods is just a rough guide. You may find you need to eat less than half (like me) or that you can eat more than half like others.
As you get into it all and read around the forum you may see people talking about carb counting. If you want to understand what that is just ask. It is a powerful weapon that a diabetic can use to control their condition and one that many of us use to great effect.
Good luck and keep asking questions.
Regards
Steve
PS Here's two good links about what's good to eat.
First is the lady doctor who's low carb / low GI recommendations seem to form the basis of what's recommended in Sweden
http://blogg.passagen.se/dahlqvistannika/?anchor=my_lowcarb_dietary_programe_in
Second is a good beginners guide to low carb regimes that are excellent for reducing blood sugar levels and losing weight.
http://www.dietdoctor.com/lchf