Go for HOMA IR2 test and C Peptide assay to know the insulin resistance and insulin levels. Is there any symptoms? You weight and associated symptoms matters more. Your dietary habits are also important for proper evaluation.

Yes your insulin levels can be high in spite of your blood sugars being normal, especially when you are on the way to being diabetic in the future. Post food sugar levels need not necessarily be higher than fasting levels. You shouldn't get that test done without consulting a diabetologist as a clinical evaluation is most of the times more than enough.