It depends on how much you failed by, how they will handle it- sounds like you could be considered boarder line, in which case, they will have some recommendations for you on what to eat and what not to eat, but you won't be diagnosed with gestational diabetes officially.
Im in connecticut over here is 1 hour dont pass 3 hour i had to do mines 3 time i fail 1 pass 2 but my docotor not concern neither just drink alot water cut the soda juice and sugary stuff out i did 1 month and they did another to see how i was doing and i pass just do what your doctor say and be careful of what you eat