CDG,
How long and how much Zoloft were you on? There are alot of withdrawal symptoms from SSRI's from extreme to mild, and should be tapered very slowly. If you are totally off of it, definitely dont go back on it to rid the withdrawals. Common complaints of withdrawals, which people relate to relapses in panic, when its the withdrawals are, migraines, flu like feeling for 3-4 days, breaking out in a sweat, hand tremors, nervousness, agitation, etc. Im not a doctor but if your still taking Xanax on a as needed basis, use this during the times of high anxiety, or situation provoking, ie anxiety about leaving your safe place. Once your ok with leaving your home, traveling then taper again, please keep the breathing techniques up daily even when the panic is gone, its one technique that benefits everyone panic or no panic in stressful times.
Trish