Failed one hour glucose test, what to expect?

I failed the one hour glucose test with a score of 141. The nurse on the phone didn’t explain if it was overly high or anything. She told me to schedule a three hour test at a lab Corp and we will go from there.

But when I asked if there was anything I needed to prepare for she just said schedule it and unfortunately up. I’ve tried to call back and ask another nurse but no one has answered.

Do I have to fast before?

Are my levels dangerous?

What happens if I do have gestational diabetes? I don’t know anything about it and I’m scared to google.