Usually, up to 20-30 point different can be seen between glucose levels noted on glucometer and the glucose level seen in lab for fasting, random and pp values. HBAc is average of all fasting, random and pp sugars over the past 3 months, your levels is perfectly within normal limits, ( should be less than 5.7) without any signs of prediabetes or diabetes. You lab levels should be less than 125 for fasting and less than 140 for pp to be considered free of diabetes or prediabetes. I would not take too much stress about your home glucose readings and continue to follow healthy diet and regular exercise. Check HbA1C every 6 months. Monitor for symptoms of rising sugars such as increased thirst, weight loss, increased urination and increased appetite.