you know, the more I think of this the sadder I feel for your DD, and the more angry I feel at the way you handled it.
I was made to feel dirty and disgusting by my aunt when I started my periods (my aunt raised me), and I was not allowed to have a bath or wash my hair when I had my period and also had to wash all my own clothes (my undies by hand), as I would contaminate the rest of the family. I had a hidious time, and it make me even more sensitive regarding my own daughters and reading about other teen girls.
It is horrible enough for them starting their periods really. It is not exactly made nice for them at school half the time as school toilets are so unhygenic, and then add in a mother without any comapassion, what a dreadful time.
I have only one rule with my DD1 regarding her period, that she feel able to talk to me without embarrasment as, at the end of the day, I also have periods as to all women, so it is a natural process that we all go thro.
Oh, and another rule, she needs to let me know when she is 'on', (and vice-versa), as then we both get heads-up on when the other will come on........we are within 24hrs of each other now!