Diabetes

So around 12 weeks pregnant, I was told that I have diabetes. They think I possibly had it before pregnancy but are not too sure. My question is for those who have experienced this is how long did you manage your diabetes before having to be on medicine or insulin? So far I’m right about to be 18 weeks and have been managing with diet alone. My numbers are really good. I’m just getting a lot of anxiety thinking medicine or insulin is inevitable and soon, my numbers won’t be able to handle with diet alone, it’s driving me crazy.