I think the best medication for prolonged anxiety is klonopin..it directly effects the anxiety centers in the brain. The other two medications effect anxiety secondarily, not as strongly. Your best treatment is a combination of therapy and klonopin.
Prozac seems to be indicated for many mental illnesses.
I've found short courses of lorazepam useful for anxiety. Clonazepam is OK too.
What I've found best for anxiety however has been exercise and relaxation exercises (deep breathing, music, progressive muscle relaxation if repeated regularly, etc) and of course therapy. I found my fears of dying were greatly allayed after talking and working through some of the issues in therapy.
Be patient during this medication transition period. It's possible you may feel more anxious for a bit but go with it and try to work through it. You should feel an improvement with the medication. If not, talk to your doctor again.
Good luck.
J
Make sure you taper slowly off the Paxil before starting the Prozac, so you can separate the symptoms of the body adjusting to the lack of Paxil from the effects of Prozac. There's no predicting what Prozac will do for you, anymore than you could have predicted what Paxil would do for you. Paxil does have the reputation of being a stronger med for anxiety, but you're the only you there is, so who knows? And are you in therapy?