5-HTP is wonderful for anxiety. It's an herb that balances out the serotonin in your brain helping you to achieve more of a balance, thus lessening anxiety. And it helps you sleep better at night, which as everyone knows if you don't sleep well it can make your anxiety (or any other health problem) much worse.
Find something that you really have to focus on like reading. I tend to go to WebMD and read about what is ailing me and then I seem to calm way down. I think that it may have to do with getting your mind re focused on something else or realizing that what is going on isn't as bad as you might have imagined it was.
For panic attacks and anxiety, proper breathing is an art that is hard to master but does a world of difference! Notice that adults tend to breath incorrectly, from their chest/rib cage. During attacks, people tend to hyperventilate and get too much oxygen. Breath in slowly to the count of 3, hold and then breath out to a slow count of five. Do this while sitting upright or laying flat with your hands over your stomach. Make sure your hands rise with the breaths.
Practice this at least 2-3 times a day for about 3 minutes. And use whenever you have a panic attack. It helps greatly.