Hcg levels

Britt • Mommy to be
I'm 9 wks pregnant. My last ultrasound the baby was only measuring at 6wks 3 days. Heart beat was at 122. I talked to my Dr today about blood work I had done on Tuesday to check my levels. Dr said the levels are going up but not doubling. So I still may possibly miscarry. Anyone else experienced this and what was your outcome.