big baby on the way

Is anyone else having what looks to be a massive baby and is terrified? First timer here. At our 12 week ultrasound baby measured on the 97th centile. I have been measuring 1-2 weeks ahead on fundal height for a while and again at our 19 week anatomy baby is on the 97th centile. I checked the centile charts for baby boys 0-2 yrs and the 97th centile is a whopping 4.2kg 😰 I'm so grateful and blessed to be carrying a healthy baby boy but frightened of his size and my poor vagina! This is my bump at only 19 weeks... what will 40 look like !!? 😳