I agree with Pegasus and Rohag. The problem is the receptionist not your therapist. It's hard to find a good therapist that you can relate to.
Talk to management or maybe even the receptionist when seeing you will remember that you did pay.
Meanwhile, work on some relaxation techniqes. Good luck and I'm so sorry this has happened to you twice.
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Bipolar I, Depression, GAD Meds: Zoloft, Zyprexa, Ritalin
"Each morning we are born again. What we do today is what matters most." -Buddha