HCG diet and BFP?

I had my last injection of HCG last Wednesday, the 14th. I tested positive yesterday afternoon but don't know if it's lingering HCG or a legit positive. AF was supposed to show a Friday, 12/17 but still no sign. I can't find any solid info on when the hcg diet injections should be out of the system, and of course the clinic is closed today. My dr won't see me til 6-8 weeks past my last period,  but I am really not looking forward to waiting another 2 weeks for confirmation. Anyone have any experience to share??