My baby has very little words

I know this is not a question that everyone asking but I’m really worried my baby girl is gone 2 sense November she has very little words mostly she says Dada and sometimes out of the blue she says a few different words and when u ask her to say it again she stops she might not say a world only dada for a few weeks for example last Xmas everything was mama that stop after a wile and turn to dada then she became a big sister and she cud say sister and that has totally stopes now she marking a effort in talking and everything coming out all jumble up I’m scared that she won’t talk I had her check by the health nurse and she says everything is fine she understands everything like if u say give me your bottle she give it to me please has this ever happens to anyone before I’m really worried