When having a panic attack and/or wave of anxiety breaking over you I recommend grounding yourself in your senses. Even using your fingers to root what you say in your head. Puts up thumb, I can feel my feet hurting from standing all day. Puts up pointer finger, I can hear...Put up middle, I can taste...Puts up ring finger, I can smell...Puts up pinky, I can see...Usually do what you see last as this works best with eyes closed if possible.
Another emergency measure is popping something with an intensely strong flavor. War heads work great. If you don't want to mess with candy, hot sauce directly on your tongue works too.
Hope you find some relief!