Can you please define normal blood glucose numbers three hours after eating?

Less than 140: Similar to glucose level after 3 hour ogtt , may not be as accurate.

Fasting normal: 65-105 when drawn out of a vein while fasting. Various authorities have different "normal" levels. There are, however, no exact cut-offs, it's all a continuium. Finger sticks are not accurate enough for diagnosis. Two hour post meal should be less than 130-140, and any glucose >200 at any time suggests diabetes. An a1c >6% is also suggestive and needs further evaluation. See diabetes.Org for info.