I practice a lot of mindfullness breathing exercises and relaxation techniques that work for me when I get stressed, or anxious. Staying focused on yourself and how you can block out what is causing the anxiety, for me, took some time and effort but I was able to achieve that goal. Also helps me when I can't fall right to sleep, or wake up in the middle of the night. I carry my phone and headphones with me also, it helps block out the surrounding noise, so I can focus better. I hope that gives you something to look into. GL :)

Talk to a sympathetic co worker, go outside and walk quickly around for 15 minutes at break or lunchtime.

I try and change the brain patterns. IE music, painting, work, touching things with a unique texture. OR see 5 things touch 4 things hear 3 things smell two things and taste one thing. it semi stimulates the brain in several directions making it harder to focus on the flight sense.

if you have no xanax or similar med then take five mins to go somewhere quiet preferably outside in the fresh air and practice deep breathing and mindfulness on your own allowing yourself to be as still as you possibly can. maybe thing of something/place or person that calms you. then you should be good to go. sometimes a quick call to a friend/pdoc who can talk you down can work very well too. good luck with it.