Wow, that is a rather blunt response... and so terribly short. I haven't e-mailed my T very often so far, but she always replied with "Dear ...." and at least a few sentences. Even if there's not much time, I don't think an answer this short is handling the situation well,
especially if the T knows they're dealing with someone very sensitive.
I'd react the same way and I'd probably panic and e-mail again as well, so I'm not judging you there.
ETA: I think I'd even prefer the T not answering at all and instead talking about this once more in session than sending a reply like that that's perceived as hurtful.