Speech therapy

Hi ladies. I need some advice from all of you. My lo is 19 months old. Her pediatrician expected her to say about 20 words this age. But my baby says about 7 words. So as per ped advice we took her to speech therapy , they evaluated her n said she qualified for this program she doesn't need speech therapy yet we will wait for couple of months to see how she progress. We felt happy. But iam still worried about her speech. She doesn't know shapes n colors,animal sounds. Most of kids by this age should know few right. So as a parent are we lagging behind n sje is our first child. she knows 2 body parts thats all but she follows all instructions n understands most of things we say . Iam worried mommas. Is this normal and any suggestions pls n any experience with anyone of your kid? TIA