Hi, well done on the Hba1c.
There is not a simple test but a combination of tests all of which are not normally done for a diagnosis of T2.
However an insulin levels test as part of a full blood panel test. Or a c-peptide test, to see wether you have normal levels.
If you do have insulin resistance, the likelihood that there will be, higher than normal insulin levels and that is not good.
Circulating insulin levels is cause of T2.
Usually as your Hba1c levels comes down, your insulin levels and your insulin resistance decreases. Dietary control is the best treatment.
I would advise about asking your GP, but in the present circumstances, I doubt that you will get priority anytime soon.