HCG rising but not doubling?

My hcg rose from from 110 at 4 weeks to 155 at 4 weeks 2 days. Does this mean a miscarriage is imminent? :( I'm brokenhearted and need some support. I saw a similar post earlier but didn't get much out of reading it. Any advice?

***My doc said this is a 50% rise? Not 60% which concerns me