bump size

Elizabeth
Hi all, looking for some advice. I'm 29w 5d pregnant. My doc said that my uterus is measuring perfectly, but my "bump seems small" and I lost 2 pounds. She ordered a growth ultrasound to check baby's growth. 2 pounds seems so meaningless, but maybe it isn't? And a small bump? I thought all bumps were different. Has anyone ever experienced anything like this?
Thank you!