Chemical or fake?

Hello ladies, I come to you for opinions based on your experiences, as I think I've heard some crap info today from an infertility specialist. I've had, what it appeared to be a chemical, in December: tested positive on urine test, then tested HCG from blood and it was very low, then AF came extremely heavily a couple days after, so diagnosis was chemical pregnancy from my normal OBGYN. Went to this specialist and showed/told him what has happened and he said it was not a pregnancy...that my body produced HCG due to hormonal imbalance, but there was no fecundation. I've never heard such a thing, and yes, I've tested myself and do not have any tumors or autoimmune diseases which might increase the level of HCG. Been to the endocrinologist and they also said it was a pregnancy which stopped from evolution, but never doubted the conceiving part. Have you ever heard such a thing? Thank you very much!