HPT after Embryo transfer?! Help!

Ann
Had a FET with one genetically normal embryo on 6/7. Was going crazy and  I couldn't wait until 6/20 for my HCG and took a HPT today at 8 days after FET...OMG there's 2 lines😅!!! Any Circumstances under which this could be a false positive? Didn't have any HCG containing meds since it was a FET, just on daily IM progesterone and Q3day IM Estrogen....Want to be ecstatic, but so afraid to let myself go there until I see the doctor for the HCG and US😭