Ugh...I am sorry to hear this...attacks are so miserable!
Can you pinpoint any new stressors that you are currently dealing with...even just small emotional triggers that could be sparking this?
a hormonal connection?
Have you backed off of your self help practices because you were feeling well for a good period?
If you've done all the troubleshooting you can...then maybe it's time for an eval with your psych? How long has it been since your last one?
"Courage is not the abscence of fear, it is feeling afraid and doing it anyway!"
"Worrying does not empty tomorrow of its troubles...it empties today of its strength."
Corrie Ten Boom
Panic Syndrome recovery due to CBT