L.B.
With my first pregnancy I was 5 points over on my 1 hour and slightly elevated on my 2 hour reading of the 3 hour test. If you are elevated at all with your 3 hour, they will probably have you do some tests where you go in having fasted all night, they take your blood, you eat a regular meal then 1 hour later they take your blood. I was OK on those tests. I was able to control mine completely with diet. As was already said, NO juice and no simple carbs 1st thing in the morning, that includes milk. All other fruits and milk should be limited and eaten with protein. But they will give you information on all this. I have since had 3 more children with no gestational diabetes. If you are careful, you are probably in good shape for this to stay a minor issue.
HTH