20 week detailed scan- fetus with big head circumference and big adominal - gastational diabetes?

I just did a detailed fetus scan at 20th week. Results showed that baby has big head (max reading) and big adominal (max reading). Baby weight was on the high side also. I'm so worried as I read online that these are symptoms for babies with ASD and usually shown at week 20 onward. Another possibility is I may have gastational diabetes. So worried till I couldn't sleep well for the past 1 week. Anyone has similar experience. #gastationaldiabetes #asd #HC/AC