Probably you are having impaired fasting glucose
Your fasting blood sugar should be normal if you had fasted for 8 hours. Sandwiches and orange juice should not have affected it if your glucose metabolism
You have told that your after food sugar values are normal. Did you recheck your fasting blood sugar?
If it is still high you should take treatment.
Now treatment needn't start with Insulin
First step would be weight reduction if you are obese.
Start on aerobic exercises , it will reduce your weight and improve metabolism of sugar.
Cut down on processed carbohydrates ,sugar , saturated fat
Increase intake of green vegetables , brown bread , etc
In case lifestyle modification do not bring fasting sugar to normal level , drugs like metformin
can be started.
Discuss with your doctor