Small gestational sac?

Sancia • TTC 4 years, 4 failed IUI’s, 1 cycle IVF, 1 chemical, 1 blighted ovum, 2 failed FET

Hi ladies,

So went in for my 5 week ultrasound to measure/check gestational sac. It only measured 5.6mm, the doctor said that was too small and that my pregnancy is probably not viable. We drew my hcg today, my last hcg was Saturday 1,025 up from 450 the previous Monday. So it’s going up by 100’s everyday. Going to have another ultrasound on Friday to confirm. Anyone else have any experience like this?