I don't think it is that important that you need to know what happened in order to judge what you should do.

If you normally e-mail on Sunday nights about your week, and that is the agreement you have with your T, I don't see why you should change it. I know she asked you not to e-mail one day, right? But not this Sunday?

I would try and respect not talking about the misunderstanding. Have you e-mailed her in the past just telling her you missed her?