Weight gain/loss

Hi mommas. Have/are any of you had issues with weight gain? Or lack thereof? Pre pregnancy I was 189 and I dropped down to 168, and the past 3 months I’ve stayed at 170. My doctor insists on me seeing that dietician and she asks how I’m feeling and how I’m eating. And honestly I feel fine. (Normal pregnancy nausea sometimes but the vomiting has resided thankfully) and of course the usual pregnancy aches and pains. This is my third baby, with my first I gained about 27 lbs in total, she was 7 lbs even totally healthy. With my second I gained maybe 15-20 lbs, I got really thin with my second and ended up having GD and it went undetected and he was 9 lbs 6 oz. It makes me a little anxious imagining this baby being that big or even bigger.