31+6 baby b has small tummy

Courteney • Airforce wife * son 9/2018👶🏽💙* b/g twins 5/2020👶🏽👶🏽💙💖* last baby 9/2022💛

So yesterday at my 32 wk appt, I was informed that baby b( boy) tummy is measuring pretty small. Under the 5% mark that is normal. Baby girl is also small but proportional not too many concerns with her though. I’ll be going to a high risk ob to take a look at them. Has this happened to anyone ?? Both babies are weighing in fine at 3 lbs 9 oz and 3 lbs 10 oz.