Missing/ Empty sac??

Okay, 3 weeks ago when I should have been measuring at 5 weeks. My ultrasound was empty. Nothing could be seen.

Doctor sent me for blood work to confirm pregnancy scheduled 2 days apart to see if my hcg levels we rising. They in fact were, so he called to confirm and schedule a repeat ultrasound.

Today I should be measuring at 8 weeks and 5 days. However today ultrasound showed an empty sac, but this time there was at least a sac.

So here I go for more blood tests, one today and the other on Thursday to see if my levels are increasing or decreasing.

I am feeling so frustrated and now worried. I miscarried last September at 8 1/2 weeks.

I am hoping my lil one is hiding...

Anyone else experience this?