VERY Low HCG after faint line positive

I got a faint positive pregnancy test! With having had several miscarriages before, I immediately went to get a blood test. My HCG levels were only at 6. :( At that hospital, 2 and below is negative but they don't believe it's positive until at least 25. I'm hoping this isn't going to be another loss...does anyone else have experience with this? The PA told me some people normally have HCG in their system but I've had many blood draws and tests due to infertility and recurrent miscarriage. And normally my HCG is 0, so I, personally, don't normally have any in my system. He told me to come back in a week but right now he doesn't consider me to be pregnant. :(