Hcg not doubling

I found out in the begining of december that me and my husband were going to be having the baby we had been praying for. A week before christmas I woke up one morning and was bleeding BAD!! So I went to the er, they sent me to the ob, and from there they told me my levels were not right and that I was probably going to miscarry. They called me 3 days later to tell me things were still not right and to go back to the er. They told me the same thing....prepare to miscarry. I was instructed to have my hcg tested everyother day to watch for it to go down indicating i lost the baby. After this my levels started to double. 17 to 36 then 64 then 126 so they assumed i had twins and lost one and my body was just catching up. But then it stopped and has not doubled again over the weekend. They want me to take a pill to make me miscarry because they say something is obviously wrong. My husband wants me to take it because he and I are both so emotionally drained from all of this but I just dont know if its the right thing to do??? Any advise please im desperate!!!!