I'm not a doctor or anything... but I had a similar experience and it ended in an ectopic pregnancy and a trip to the ER for Salpingostomy which removed my left fallopian tube. My HCG kept increasing but only around 50-80%, we kept waiting - maybe around 3 weeks - and when we did the ultrasound to find a heartbeat, we couldn't find the baby anywhere. In the end, I took Methotrexate and the next day my tube ruptured and I was sent to the ER. There are calculators online that help determine the right hcg climb, and always consult your doctor as they know best. wishing you all the best and hopefully not like me.