First time mother nerves

Destiny
I'm currently 31 weeks pregnant with my first child a boy that I'm naming Everett ,I am facing lot of nerves about my coming labor. Having nightmares about things going wrong and just all-around concerned ,the baby is currently small for his stage and doctors are concerned he's just not growing well. I and my fiance are both small people naturally and they think it could be genetic but they also worry that since I am so small being only 107lb currently then I will have complications. Do any of the other mothers out there have some advice I can do just to help ease my concerns I'm already eating 80-100 grams of protein a day, I have been trying to exercise plenty but unfortunately I'm a little weak and still have issues. I just want things to go well ,my mother nearly passed away delivering me and my brothers and it has given me a lot of anxiety.