Hcg level drop

I had a hcg check on Tuesday due to having a miscarriage in May and my levels were 5,500. I am supposed to be 4 weeks per my last period. I went back yesterday and my levels dropped to 5,400. My doctor immediately said I’m going to have a miscarriage and have me my options to miscarry. I feel like my doctor immediately was negative about it. Don’t get me wrong he is the expert and I know that hcg not doubling and it dropping is and impending miscarriage but why so quick to jump to the options as to D and C or the pills to go ahead and miscarry. Has anyone’s levels dropped only 100 points and everything still be ok? I feel like a rollercoaster of emotions about this like when is it going to happen or like God knows what’s going on and let it in his hands and I’m sad/ frustrated.