Can this be a false positive result?

Hi there. Today, I received a letter from planned parenthood telling me that I had tested positive for my herpes test. I am devastated right now but am skeptical too. I was tested by Quest Diagnostics for both HSV-1 and HSV-2 (IGG) and both came out negative about 5 weeks ago and I was tested by our city's health department about three weeks ago and that result came out negative as well. My blood sample was taken about two weeks ago, about a week or so after my last negative test. And on top of that, both of my partners are negative with the first being tested for everything three weeks before we had oral sex (and didn't see anyone else between the results and me) and the second just got recently tested and she came out negative too (which is odd considering I am supposedly positive, wouldn't she be too?) I am really depressed at the moment and have been reading alot of info on the internet that deals with false positive test results and result errors with planned parenthood. Apparently, they don't use western blots which is the most efficient protocol to use for detecting HSV. Can someone tell me what might be going on? And why the hell PP decided to mail home a letter saying Im positive as opposed to calling me or even telling me to come in?