You posted this as a question about rent and utilities. Your landlord's occupation of another unit is irrelevant to your rent, just as it would be if any other tenant moved into the other unit. If the basement apartment is not separately metered, you are paying the utilities and your lease doesn't define a split or contribution from the occupant of the other unit, that's certainly something you can discuss with your landlord. You haven't explained why you can only do laundry on certain days.
If you want to know if the basement apartment is an approved housing unit, check with local housing officials.
If your landlord's records show you owe a certain amount of rent, and you agree that the records are correct, then that is the amount you owe. If your landlord claims you owe a different amount, obviously you would challenge her claim based upon her own records.

