If one hears mother of God how does one know it is limited to only Christ? Why would the term not apply to the Father and Holy Spirit?
Did Mary conceive God the Father in her womb, and give birth to him? Did Mary conceive God the Holy Spirit in her womb, and give birth to him?
As those two questions make clear, only a person who knows LITERALLY NOTHING about Christianity could fall into the error you are concerned about. Obviously, the proper response to total ignorance of Christianity is instruction in Christian dogma.
Usually if someone uses the term God it is considered as God the Father unless further qualified.
It’s one of the subtleties of Catholicism to call Mary the mother of God.
It helps deify her as the Queen of Heaven and the Forever Virgin sinless One