The additional money has been applied to the SD even though
the amount you gave her exceeded what you owed.
The amount your questioning can be applied to the rent, she
can do that if she wants, it's her building. If she chooses not
to it's collecting interest, so remember that for the next rental
increase. Never hurts to ask questions, I know she seems
a bit militant, but don't let her intimidate you, it's just a
tough act.