Okay, so it sounds as if you have had a doctor diagnose you with anxiety...well, then you can really start to focus on using coping techniques to help yourself.
Like I said, we have a great Resource Guide here on our main page...and I will copy some breathing/relaxation exercises for you below.
If you find that you need further help, asking your doctor for a therapy referral is another step that you can take.
Give these a try though, see how you feel and keep posting with us...it does help! Here are a couple of links that teach some breathing and relaxation exercises, and I'll post my favorite 'The Divided Breath' below...
http://www.healthyplace.com/
http://www.stress-relief-exercises.com/
http://www.ehow.com/video_4405003_breathing-exercises-panic-attacks.html
http://www.psybersquare.com/anxiety/panic_relax_I
Okay, my favorite is this one, it takes some practice though. When I first started, I could hardly do one!
The Divided Breath:
Imagine your lungs as having 3 parts. The bottome third, the middle, and top third. On the inhale fill the bottom third first, then the middle and finally the third. Make sure that this is one continuous breath, but divided, with a slight pause in between each third. Hold the breath in for 3-5 seconds if possible. Exhale in reverse. First blow out the top third, then the middle, and finally the bottom third of your lungs until all air is expelled. (remember the pauses) Repeat several rounds for a toatal of about 10 minutes. Practicing this every day will not only give you control and structure to your breathing, it will strengthen and loosen the thoractic muscles, allowing better, more productive breathing, and relieving the chest tightness!
Good luck, and remember to pracitce everyday whether you're stressed or not, that way when anxiety really shows up you'll be ready:)
Scaredy Cat