Just to clarify was the 14.8 a result in % from an HbA1C or from a finger prick test which would be in mmol/l. THe HbA1C is the test used for diagnosis and is an average over the previous 3 months, however if that is what it is then you are well into the diabetic zone as the threshold is 6.5% which in new units which your doctor should be using would be 48mmol/mol
If that was also a finger prick the units would be mmol/l and is still high. Normal expectation is 4-7mmol/l before meals or fasting (morning) reading and no more than 8.5mmol/l 2 hours post meal. If starting levels are higher than that then the aim is no more than an increase of 2-3mmol/l 2 hours post meal.
If you levels have been quite high then it is better to bring them down slowly to avoid any eye or nerve issues some people can get.
I know the temptation is to want to do it quickly but gradually can be better.
Do have a look at the Learning Zone as things will be explained to give you a better understanding or this link might be helpful.
https://lowcarbfreshwell.co.uk/