Hcg doubling time slowing

My hcg on 12 DPO was 52, 14 DPO was 201, 21 DPO was 5363. Now on 27 DPO it is 33,826. It was previously doubling every 30-36 hours. Now, sometime between the 5363 result, it has slowed to about a 54 hour doubling time. What does this mean?? Should I be concerned? TW I had a miscarriage right before this pregnancy and I never passed 1,800 hcg. I’m so scared now.