I was just diagnosed 2 days ago, but I have no idea what to do!

My midwife clinic basically called me and said I have gestational diabetes and that someone would call me to set up an appointment with the diabetic clinic. 2 days later and no one has called me.

I don’t know what I’m supposed to be doing! I’m trying to eat well but I’ve still had one piece of chocolate yesterday and today and I feel so bad but all I want is junk and I don’t know if I’m allowed a little bit or nothing 😭

Can anyone give me a basic rundown of the diet and what I should be doing until I can get an appointment??