http://www.drugs.com/propranolol.html

The metallic taste can be a side affect of a medication. But check the side effects. Make sure your not having any of these first, just be aware of how your feeling. It might be a good idea to try and write them down.
We use this web site a lot at work.
When I have an attack, I also get that "swimming" feeling in my head. Splash some cold water on your face and try to focus on something positive. I mean, REALLY focus. I know it sounds impossible but try as hard as you can. Sometimes, it helps for me.