I'm not an expert on panic attacks, but I do have them. With me, I can't figure out what
triggers the anxiety. It comes on so suddenly.It is very frightening. I think it's being around too many people. I don't like crowds.

I do know a couple of things that help me. I go outside, away from the crowds. I take deep breaths and try to stay focused on breathing. Another thing is creating a distraction. Keep a small object in your pocket. When you need a distraction, reach into your pocket and touch the object. Feel it's texture, smooth or rough, bumpy or soft. Just try to keep your thoughts on that for as long as you can.Usually it is enough to get by.
I hope this helps.