I think it’s your responsibility as a mom to be worried
My opinion: don’t worry too much. Kids do develop differently and just because Sophia is a little behind right now, doesn’t mean she’ll be behind later.
But to add, I do know of two factors that might delay speaking:
1) A child is introduced to more than one language
2) If parents don’t constantly talk to the child when they’re a baby, children might also start speaking later
(I personally know a mom who didn’t talk to her boy (now 3 years) when he was a baby because she didn’t know how to “talk baby talk”, so now that he is three, he doesn’t say a single word, but understands everything.)
I don’t know if the above factors effected your little girl or not, but even if they haven’t, I’d probably wait a few more months and see how she progresses before beginning to worry.