Dating

Porsche

Went into my first appt today thinking I was between 5+3 ( conception date) and 6+1 (last period). I ended up only being 4+5 from measuring gestational sac. There was something in sac but it wasn’t identifiable. They told me everything looked normal for the 4+5 measurement but I know i should be at least 5+3. I’m really worried about miscarriage.