Chance of not being diagnosed when I should have been?

I’m so sorry in advance if this post is insensitive because I know this whole group is full of people actually struggling with GD.

I joined the group after failing my 1 hr glucose test with a 170 (passing at my doctor’s office is 139). I didn’t eat breakfast before the test but I did have rice for dinner the night before around 6:30-7. With my first baby I failed the 1 hr with a 150 because I ate an English muffin for breakfast that day. I ended up passing the 3 hr that time. But considering I didn’t even eat breakfast this time around and failed with such a high number, I was convinced I actually had GD this time. I have a family history of diabetes so it wouldn’t surprise me and I figured I couldn’t have gotten lucky twice. But then I passed the 3 hr this time around as well. I was honestly super shocked.

My first baby ended up being 9 lbs while I’m a fairly small person. One of the OB’s at my office seemed really surprised that I didn’t have GD or diabetes before getting pregnant. I went into labor with my first at 39+3 (unusual for a first pregnancy) and he also had a hard time during labor and was in distress for a bit which ended in an unplanned C-Section. Because he was big he had to have his glucose tested constantly the whole time in the hospital and we couldnt leave until it got down to a certain number. Im not asking for medical advice but just from your personal experience, do you think it’s possible to not be diagnosed but actually have GD? Or am I overthinking? I would just hate to be putting my baby and myself at risk over the next 10 weeks and have no idea. Thank you!