Too small for almost 19w?

People keep saying I'm barely showing. This pic is 18w5d according to glow. I keep getting worried because I wonder if Bump should be bigger since I'm so short (barely 5'2"). And it hasn't changed much in the past couple weeks. Doc says uterus is measuring with right weeks, and I've gained 12 pounds. But belly just barely sticking out for being half-way thru pregnancy. any thoughts?