Baby loss

Hi I'm pretty new to this but I went for a scan 10 days ago and they couldn't see a defenate heartbeat I went back today and they pretty much said the same I think I should be around 7 or 8 weeks by my dates but they said they baby is still measuring around 6 weeks they said it has grown a little but not as much as it should, ive got to go back in 10 days and they said it could go either way, has anyone had any think similar?? X