At 9 weeks of age, she has a bladder the size of a pill bottle and bowel about the same. She can't hold it at all. When she feels the urge to go, her brain releases the valves on one or the other. They will fill and be emptied countless times during the day as this is when she is eating more than she will at any other point in her life (in proportion to her size that is).
As she gets older, that little part in her brain that signals the need to toilet will mature and allow her to hold on and she will have more control.
At the same time that she is maturing, you need to teach her the appropriate places to go to the toilet.
You must restrict her access to most areas of the house and gradually increase the area as she is able to hold and control her bladder and bowels better. She will be not be trained fully until she matures.
By 3 months you will really begin to notice she is partly trained, by 6 months you can have them pretty reliable and by 12 months they should be almost rock solid.
The joys of puppies.