Glucose test!

So I've never done anything like this before...asking other people (strangers) questions... But as I've asked all my previous pregnant friends they've all never had to do this ... 
I took the first glucose screen test on Tuesday and my glucose levels came back high.. So that means I have to do the 3 hour glucose tolerance test.. I am feeling out just a little because no one that I know of has had to do the 3 hour test before! So I'm asking you ladies that if you have PLEASE help relax me some! I am so nervous that I am going to end up with gestational diabetes and I'm not going to be able to lose it! As if adding a new baby into the mix wasn't enough an entirely new diet is frightening! 
So if any of you have been through the second test and you ended up in the clear or not please help calm me!