Mamas w/ anxiety!

So tonight while we were out at a close family friends "Desserts with Santa" thing tonight, I had a terrible anxiety attack, hyperventilating/balling my eyes out/shaking, I could feel it coming on when we first walked in, I think it was because of all of the craziness overwhelming me at once. My question for you if you have bad anxiety is, what is something you do if you feel your attacks coming on? I usually just completely shut down and zone off and try to not think about it, but today it didn't work. Trying to figure out if there are any other techniques. Thanks in advance!