Measuring “skinny”

So I’m 37w 1d today.. scheduled for csection on October 6th, 5 days before my due date. I had my biophysical done today and was told baby boy is measuring “skinny” at 5lbs 8-9oz (and it can also be +\- 13 or so oz) and he’s 9th percentile. So now I’m having ultrasounds twice a week til he’s here. I had placenta previa so I have had monthly ultrasounds since about 18 weeks, and he was always measuring Right on target at those. My placenta previa cleared up so I went 6 weeks without an ultrasound and now they’re saying he’s “skinny”.. now I KNOW this is only an estimate, he’s very squished and his head is extremely low.. my question is though, any other mommies go through this?? I just need some positive experiences so my S/O can feel a little better lol cus he’s freaking out.