Hi I recently gave birth a month ago to a little boy who was in the 1%tile literally my whole pregnancy.. he was born full term at 3lbs and he is now around 5 pounds and is thriving!! I wouldn’t worry too much if I were you.. it can definitely be scary. But your baby also has along time to go and can go from the 1%tile to 20th in a month! Mine had went from the 1% to the 16th in 2 weeks and closer to my due date he had went back to 1%
Ultrasounds are more than 80% inaccurate. So many stories of them being wrong when cause of induction / c-section etc, it’s very worrying and upsetting. Try to find some calm in that knowledge xxx