If i have gastritis and the stress of possibly getting sick makes me feel worse. would anti anxiety medication help at all?

It depends: Gastritis comes from many possible causes, with "stress" among them. However, antianxiety medication is not the first thing i'd reach for. You may benefit from some help with self-calming -- a good therapist can help you with this. Also breathing exercises, meditation, yoga, and other things you can do on your own. See http://www.Healthjourneys.Com/ for some helpful recording you can get too.