Possible blighted ovum and terrified

[Bss20]

Hello just looking for some advice and if anyone else has had a similar experience. 

So I took a pregnancy test on the 5th of November it was a clear Blue weeks it said 1-2 weeks pregnant. Was super happy! Fast forward I had a scan on the 17th of November should have been 6 weeks however was measuring 5 weeks they could see the gestational sack but no yolk sack or fetal pole. Told me to come back in 2 weeks. My hcg was 3500. 

I’m so confused because surely if I tested positive 2 weeks before the scan I should have been measuring 6 weeks pregnant not 5?! Absolutely worried sick does anyone have any advice? Or similar thing happen to them? 

Thank you x 

[MrsNandortheRelentless]

Dates could be out. It’s not unknown.
Go back as they suggest in 2 weeks, you will know for sure then.

[Soph871]

I’ve just been told the exact same at a scan. Did your next scan go ok? x

[Bss20]

@Soph871 yes! I’m now 25 weeks pregnant with a baby boy! X

[Bss20]

@Soph871 wishing you all the luck for a healthy pregnancy x

[Soph871]

Ohhh congrats lovely! I hope the rest of your pregnancy goes well and anxiety free! xx