1. No need to make any changes to your diet. My doctor did have me fast 10-12 hours before my 3 hour test, so if you didn't do that before you may need to do this time. No food, but I could drink water. 2. According to my doctors, you 100% do not have GD. 3. I failed the 1 hour test and passed the 3 hour test with both my kiddos (currently 26 weeks pregnant). I will give you a quick heads up that the 3 hour test made me feel a little loopy during hour 1 and hour 2, but I felt fine by hour 3. Once I got home and had lunch, I felt extremely tired and needed to nap for a couple hours. Your experience may be completely different, but I thought I'd mention in case you have the same experience and can plan to take it easy the rest of the day.