Measuring 41 cm at 36 weeks 1 day😰💛

Brttny💕 • Mother 3...9 year old Girl💕🎀....2 year old boy 🙉💙...and new baby girl 💝Due Nov 9th
So I went in today and my doctor says I'm measuring 41 cm. Of course that freaks me out!! Instantly thought omg Baby Bri must be gigantic lol. Had an ultra sound just to check baby only measuring 6 lbs 3 oz...what does this mean?? Has anyone else experienced this??