Susan, this is a tough case.
I would suggest that you need to get a second opinion. Try another GP
initially, tell him/her your story and see how you go.
You can change GPs at anytime. You dont even have to tell your
current GP you are doing it, so long as you are totally honest with the
new GP.
Worst case scenario, you can always go back to the old Dr, but its quite
likely you will get some better advice. If the GP cannot give you advice,
he really should be referring you to a psychiatrist or a Dr with some
specialisation in mood disorders and psychiatric medications.
Small doses of SSRI antidepressants do work for some people. Its
unlikely that a small dose will agitate you a lot, but some people are
hypersensitive to various drugs.
In terms of how you feel, its quite possible that celexa wasnt the right
SSRI for you. Different pharmacological treatments are used for
different patients, and unfortunately there is a lot of trial and error
involved in finding the right drug for some people. Evidence shows
though that most people respond better to one drug than another.
Prozac may well be a much better choice for you than celexa. If it is
the more upbeat, stimulated feeling that works for you, something like
zoloft may be a good choice too.
Anyway, try a different dr, that is my advice.
Remember that the key to anxiety disorders is generally catastrophic
misattribution - we tend to misinterpet natural changes in our body, or
even in the environment around us dreadfully, and spiral into anxiety
and panic as a result. Agoraphobia develops as a result of
systematically misattributing a coincidental activity with panic or
anxiety. It is the fear and the misinterpetation that is the problem.
Always remember that it is far more likely that your anxiety is making
you think you have another illness than you really do have that illness.