Can A Miscarriage Occur If An Eight Weeks Old Yolk Sac Collapses?

I was told at 8 weeks my yolk sac collapsed & even though my hcg levels keep rising they re nowhere near what they should be. My doctor said I would miscarry my baby, and she knows no pregnancy that has ever recovered after these things. I m wondering how true this is, and if there s a possibility I m not as far along as what they think I am. I am not bleeding accept for a lil dark brown sometimes when I wipe after going to the bathroom. I have some slight cramping off and on, but other than that I feel and am completely healthy. I really appreciate any advice or knowledge you can share with me. My doctor wants me to schedule a D&C, but I m not ready to give up so quickly! Thank you for all your time & energy in helping me.❤