no heart beat

hello any advise wil be greatful i got pregnant but couldnt remember when i last came on i worked out that i came on my period in july but couldnt remember having a period in august so worked out my date from there when i was booked for a scan i thought i was 13 wks pregnant but whenthey did the scan she said there was no heartbeat and that i was 8wk 4 days pregnant ,i havent had any bleeding or pain and th nurse told me iv got wait 2 weeks to see if i bleed if not iv got go for another scan and discuss having a d/c,iv read that sometimes scans are wrong and am so scared as wev waited 7 yrs after my little girl to have another baby ,