It's more like if you accept it, it may fade. Anxiety is a feeling, so you can't control it directly, and there is not a special math kind. You have a learned response and just have to unlearn it. That feeling in your stomach cannot hurt you. Just sit and have a feeling. Stop thinking the fear is a bad thing. It's trying to protect you; it just happens to be wrong. Teach it otherwise by being in front of math, not doing anything to run from it, and observing that you don't die.
Obviously the therapist is there to work out that process. Just to say that there is nothing special about math. It's just a thing you've learned is scary. Your body will feel afraid. So what. That doesn't mean *you* are an afraid person.
If you need a break, take one.