I can only speak for myself... This does seem off to me.
I failed after the 3 hour test- and I only went 2 days not knowing the results of the 3 hour (was told I failed on a Friday) and I was in to see the dietician on Tuesday. For me, it was very important that I have the right information so I could start making the changes I need to make. During that weekend I hadn't seen anyone- I made myself insane. There were so many scary things all over the internet that made me think gestational diabetes was super super serious and it's not, you can control it. When it's controlled- it poses little to not complications. My doctor is treating my pregnancy like a normal one because the GD is completely controlled.
I would also suggest to JUST look like GD menus... DO NOT look up possible complications- DO NOT look up what can happen if it's not controlled.. just please don't. I spent the entire weekend freaking out and crying. I found a sample menu I followed before I met with the dietician and it worked quite well. You will be totally okay. However, yeah, if I were you I might demand to see someone sooner than 2 weeks.