scared about gestational diabetes screening

I'm 27+3 and will be going for my screening test on Wednesday. I'm really scared. This is not my first baby and the last time when I went for my test I was told to eat whatever I do and I did my breakfast and my sugar was high so I ended up doing the 3 hour which I passed in flying colours. Now I so scared for eating anything before the screening. Are u guys eating before screening or doing fasting ??