Stagnant growth in baby bump over 3 weeks

No baby bumps are the same & that does not determine the size of your baby so no need to worry for things like that. Of course for first time mums your bump will be smaller and may show only a bit later. You'll show more with your subsequent pregnancies as your uterus has already stretched from the previous one. As long as your baby is well & healthy that's all really matters.

I don’t think a baby bump determines how well a baby is growing inside mummy’s tummy>< different people varies differently, just stay happy and don’t worry too much okay? Since ur baby is growing well there’s nothing to be worried about:)