No yolk sac at 5w 5days

Emily

Hi I had an abdominal ultrasound yesterday but only the gestational sac was found. It measured at 5w5days but there was no yolk sac. I was just wondering if this is normal for an abdominal ultrasound or if there could be something wrong. Going by my last period I would be 5w 2 days. Thankyou 😊