Hi,
i suffer some of the same symptoms too. You should try relaxation techniques, including deep breathing, imagery also yoga & or pilates can help you learn how to overcome/deal/cope with all this which in turn will reduce the affects.
You should also look into things (that each work for some people & not others, as we are all different) like herbal teas, essential oils like lavender are good for relaxing (although I personally hate lavender, like I said we're all different), certain vitamin &/or minerals like omega 3 fish oils, vitamin b6, another way to calm yourself is to take a long warm perfumed bath with some candles around (if possible).
Try to figure out when these spells are most likely to occur so that you can be prepared (for me it's often if i'm out alone so I try to avoid this!!), if out sit down as soon as you can & I find a cold drink helps, along with concentrating on breathing deeply.
You say your dr blamed it on depression but depression usually (although not always) has a cause, so are you seeing anyone (counsellor/psychiatrist even a support group) that might help you to come to terms with the underlying cause?
Anxiety is not always caused by depression (some people have anxiety attacks if they see a spider or are in a small space, because they're afraid of these things!! But they're not depressed, I can not be anywhere near trees or bushes or I just freeze & am terrified so I avoid them but that has nothing to do with my depression).
So try & see if the attacks are related to any event/place/person. If they're more generalized attacks i'd try the things I suggested above & personally if you can get it some 5htp (a supplement of tryptophan) which will help reduce stress due to the way it works on the serotonin levels in our brain.
Good luck.