first things you should remember. breathing, steady it, focus on a rhythm. remember what time it is, look at your surroundings how to figure that out. feel the surfaces around you. focus on the present state, and try and bring yourself down to earth. remember a phrase that becomes a mindset. "this too will pass"
i have panic attacks all the time, i just became more aware i've been having them. if you often have anxiety attacks on a very reoccuring basis you may need a synapic damper to help. it doesnt make you feel much better, just can lessen the onset.