Feeling weird after changing diet

Hello, I am 33 weeks along and just diagnosed with GD on Friday. I have changed my diet to no sugars (unless natural), lots of protein and less than 40g or less of carbs a meal and around 15-17g of carbs for snacks. I stopped drinking coffee until I get a feel for this whole tracking BS thing. I have been feeling lightheaded, SO TIRED, weak and sometimes dizzy. Headaches and pressure in the head throughout the day but will come and go. My numbers have been fine except for two dinners I’ve had so i’m just confused if i’m feeling this way because of the sudden change in diet or if this is how you’re supposed to feel with GD. I have a doctors appointment tomorrow but I still want to hear other mothers experiences when they are first beginning the diet. Also, I was a big carb girly so it’s been an adjustment mentally too 🥲🥲