What exactly qualifies as a panic attack? I hear people talk about them all the time, but I don't know nearly as much about them as I would really like. Are there different degrees of panic attacks? Different types? What are the most common symptoms? How about the rare ones? How long do panic attacks typically last? Etc. This important for me to fully understand so that I may determine whether or not this is something that I've been experiencing. I don't want to go to my therapist and tell them that I experience frequent panic attacks when I'm merely just mistaken, so I would be most pleased if someone with better knowledge than I were to help me out.