What Should Glucose Levels Be After Eating

148mg/dl and 142mg/dl Blood Glucose Level. What’s my diagnosis?
I did a test at school for blood glucose level. Here are the results:
FIRST: 3 hours after eating: 148 mg/dl
SECOND: 2 hours after eating: 142 mg/dl
If it’s okay, I’d want to be more specific with the activities that could have somehow affected the tests. Minutes prior to the FIRST test, I drunk a small gulp of energy drink. Minutes prior to the SECOND test, there was micturition.
(Sorry for the inaccuracies I caused for the tests. I wasn’t thinking whether it would affect the trial or not.)
What can you say about the results? Am I already diabetic or in risk of diabetes? What dietary advices can you give me to prevent diabetes? Or if I already am diabetic, what should I eat and not eat?
hAVE A DOCTOR GIVE YOU A FASTING BLOOD TEST…aLSO IF YOU ARE OVERWEIGHT – LOOSE WEIGHT. THAT COULD BRING YOUR SUGAR DOWN!
Is vinegar good at controlling blood sugar? (links in description)