It is very much worth appreciating that you got this doubt. The reason being generally people think getting low sugar symptoms means I sure cannot have diabetes. But it is not true! In some percentage (I don't remember exactly how much) of patients with type 2 diabetes, the presenting syptom is hypoglycemia!! So if any of your random sugar was more than 156 that means you can be a 'pre- diabetic' in whom all of a sudden excess insulin
released makes one get hypoglycemia. If you also have family history of diabetes, then that also justifies the doubt. get 'Extended OGTT' and HbA1c
tests done to rule out this rare form of presentation of diabetes or pre-diabetes
condition. So you should be concerned for sure till you confirm the diagnosis and then follow good diet and exercise rules to maintain your health. All the very best.