6 weeks Gestational sac only?

daisy

Is it normal to only see the gestational sac at 6 weeks? She said i measured to be 5 weeks but according to my last period im definitely six. It’s hard not to worry when it’s taken me so long to get pregnant lol but is that normal? I don’t have any pics as she told me to come back in 2 weeks. But it was literally JUST the gestational sac… no yolk or baby.