No Cardiac Activity

Hello momshies, I'm 8 weeks and 2 days pregnant. I had my 2nd Transv earlier and the OB's impression about my transv was no cardiac activity but theres a baby with head and limbs. She wanted me to repeat the scan after 1-2 weeks. Nagwoworry ako. Is it normal ba o may case ba nangyare na 9 or 10 weeks nakita ang heart beat? Please answer me ?