Panic attacks are very real. Anyone who says otherwise has never had one. It has physical symptoms. For me, the worst are the blood circulation related symptoms. My feet get extremely cold, my arms are usually the first to go numb, and then my face. Then I get tunnel vision. The only thing that helps, in addition to benzos, is having someone or something help me to stay in touch with reality.

But yeah, it can come out of nowhere, unprovoked. Usually when that happens, my symptoms are very mild, but it does happen.