Thought I would post a "know-how-you're-feeling" message.
Can't really offer you anything more as I am sure you know all the "tricks' on how to reduce the effects of anxiety without meds. On the other hand, if this is something you have dealt with before, maybe you can call your GP (if aware of your history) for an anti-anxiety medication until you can see your therapist.
Just don't forget to
keep on breathing...