Incomplete miscarriage

If I went to my specialist Aug 20 and they said I was only two weeks then I went to my Dr they had my weeks wrong and thought I was 9 weeks and did not show me the screen and couldn't find my baby heart beat it's always hard to find my babies heart beat she did a ultra sound for like 3 seconds and said my baby passed cause❤she couldn't find baby heart beat the e, r only seen one arm maybe my baby was turned backwards I go back next week to get another untra sound I pray that they find my baby heart beat my stomach still growing why and advice