Wow! Awesome number.
You are very far from being diabetic based on my limited knowledge of A1C readings. I have followed my A1C for the last 10+ years, having bloodwork done 4x/year. My A1C highest reading - 7.0 - back in ~2012 and again 2 weeks ago. It has been as low as ~5.5 over the same period. I was put on Rx meds in 2012 for Type II diabetes because of A1C level but rarely took the "horse pills". Instead, I lost weight and greatly reduced sugar intake (tried to, anyway!).
Seek another doctor's advice/consult as an A1C = 4.2 really is far out of diabetic range. I don't know though if your doctor is looking at any other numbers in blood tests like fasting sugar amount.
