Borderline HCG but BFP

Ashley • TTC #2 w/ iui. PCOS. 5 babies in heaven 👼👼. 1 handsome Rainbow baby 🌈.

Anyone had a BFP and were confirmed pregnant but have boderline or low hcg levels? I know I ovulated Sunday the 31st of July (hcg trigger was taken a day and half before) and that I implanted last Wednesday August 10th (cramping and extreme fatigue). I started getting nauseated at smells and so I took a test Saturday (August 13th)and got positives on three different types. I had positives the two following days. Monday was a strong BFP and I was excited for blood work. It came back as 9.72 or "boderline". I am pregnant but they suggested I get ready for a miscarriage. Well my period is now late and my tests are getting darker. My second blood draw is Saturday. Has anyone had low hcg and still have successful pregnancy? The doctors think I implanted earlier than Wed and that my levels are not strong enough.