Dont fret because God is in control. Whatever He promised will come to pass. Sarah was 91 years old when she gave birth to Isaac. So how much more impossible is your situation?
Genesis 21:1-2
1 Now the Lord was gracious to Sarah as he had said, and the Lord did for Sarah what he had promised.
2 Sarah became pregnant and bore a son to Abraham in his old age, at the very time God had promised him.