6 Weeks in and no detection of baby yet

Hi mamas, first time mama here. Just went for my first consultation and did a scan via the vag and to only see a small little water bag. The doctor says its a Pregnancy of uncertain viability and it might go down the way of a baby developing or a miscarriage. I am currently 6 weeks in and the doctor arranged for me to go back 2 weeks later to check again... I am kinda worried...wondering if any other mamas here experience the same thing before too?