Hello and welcome!
I am sorry to hear of your stomach issues and the anxiety cycle...miserable I know.:(
Glad to hear however that you are getting help, and that you are on your way with your new Rx.
BnotAfraid's suggestion of using coping skills along with your meds is key! Here are some to get you started:
Self Help sites with breathing/relaxation exercises instructions
Panic attack relief exercises:
http://www.healthcentral.com/anxiety/c/73076/34334/breathing-lessons/
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
Another suggestion is to ask your doctor for an anti-nausea med, or even a benzodiazepine (temporarily) to help you get through your initial break in period with the SSRI.
I hope that you find relief soon. Keep posting with us for support.:)
Scaredy Cat