I'm not diabetic (but sometimes hypoglycemic) and mine is anywhere from 70-120 ... 120 after eating and 70 in the morning. I used my bg to make sure the tester is working with new strips.
From what I have read, if you get a reading OVER 140 more than twice then you are pre-diabetic... even after eating it shouldn't be over 140-145. So one test can't really tell anything.. you have to test them at least twice a different times of the day. I got that info from Diabetics for Dummies

Great book by the way!