First us yesterday...

Sooo had my first us yesterday. Embryo measured 6w2d when I should measure 8-9w based on my lmp. Doc said the measurement was a little fuzzy, but gestational sac and yolk sac were both visible, along with what the tech thought was a flutter of a heartbeat. Had my hcg and progesterone levels tested (6,237 and 5.32). Going back next week for a follow up us to confirm our concerns....until then they’re putting me on progesterone.

Anyone have a similar experience and go on to carry to full term?