Hi Angelyn!
In my opinion, the only really reliable way of getting a diagnosis for diabetes is with a Glucose Tolerance Test (GTT). Basically, you have a fasting blood test and then drink a measured amount of glucose. You wait in the doctor's for two hours and then have another blood test. If your BG has gone back almost to its pre-glucose levels you are not diabetic - if it's 11 or over you are diabetic. If its between 7 and 11 you are borderline. This test is the only one I know of that measures your body's ability to metabolise sugar. Fasting tests just measure a point in time as do random blood tests. HbA1cs measure how much glucose is bound to your red blood cells which gives a sort of average over 2 or 3 months. The trouble is, all these tests are affected by other things. The GTT measures against the baseline of the first blood test and directly measures the result of sugar consumption. I don't know why doctors don't use this test more often - I guess it must be expensive. Anyway, ask your dotor for a Glucose Tolerance Test.
Smidge