My one peice of advice which has helped me a lot, give up caffine. My doctor told me that caffine speeds up your heart rate which makes the panic attack all the more worse than it is. I have not touched caffine for about 3 years now and have felt so much better for it.

I'm also taking St John's Wort, it seems to be helping and I'm a lot better than I used to be.

You say you has something on this morning that was causing you a bit of anxiety, it was probs that that brought on the panic attack, as like you I dont have to be thinking about something that has caused me anxiety. Flying gives me panic attacks, was not too bad on last years flight and maybe the 2 hour stopover helped me as it broke up the 12 hr flight.

And when I do have a panic attack i get the whole sound amplified thing going on, it's not nice.