In Act 2, Scene 1, how does Anne describe the changes in the people in the annex?

From the text:

We are all a little thinner. The Van Daans’ “discussions” are as violent as ever. Mother still does not understand me. But then I don’t understand her either. There is one great change, however. A change in myself. I read somewhere that girls of my age don’t feel quite certain of themselves. That they become quiet within and begin to think of the miracle that is taking place in their bodies. I think that what is happening to me is so wonderful . . . not only what can be seen, but what is taking place inside. Each time it has happened I have a feeling that I have a sweet secret.