It's their job to take care of you in the ER. Don't ever feel shame about your condition. You did not choose to feel these panics.
I also get a pain in the middle of my chest sometimes,and sometimes my throat gets stiff,and sometimes I don't feel like I am breathing right. It may last for several hours sometimes.
Did you see that movie"What about Bob"? Bill Murray was walking around with a fish in a bowl,and had panic problems. Richard Dreyfuss was the PDoc. He was selling this book called "Baby Steps". Humor is good as you know. Brokenfriend