Still quite a flat tummy 19w3d

Danielle • Mumma to 3 beautiful Boys 🥰
Any other ladies can relate? I feel like I'm still quite flat.. do I look like I'm on the small side for nearly 20 weeks.. I do have a long torso but still.. have seen a lot more bigger bellies than mine.. Every one always comments how small i look too. I Googled and I'm worried about low fluid.. I have a scan on Tuesday.