Look up Grounding Coping Skills! There are so many, but they help when you are having an anxiety attack. My favorite is the 5-4-3-2-1 technique. Acknowledging 5 things you can see. Try to look for details in whatever you are acknowledging. Acknowledge 4 things you can touch, but actually, touch them. Acknowledging 3 things you can hear, 2 things you smell, and 1 thing you can taste. Usually, by the time you get to number 2, your mind is more relaxed due to you no longer focusing on your anxiety or what triggered it. I also encourage implementing a breathing technique while you do this activity. Inhale for 5, hold for 3, and exhale for 8 which would else help with reducing your heart rate. Holding a piece of ice for 3 seconds also can help.