Just had my ultrasound! Due date changed again!

Went in last week thinking I was 6 weeks, nope! They dated the gestational sac at 5w3d. Today a week later I went in and I was supposed to be 6w3d NOW, but my baby is measuring 6w1d! I didn’t hear the heartbeat but we SAW it and they measured it at 105BPM! Last time they only saw the gestational sac, just a week later and we have a yolk sac and a baby too! I’ve never had ultrasounds so early it was SO COOL seeing the little heart flicker! I’m really hoping this baby stays with me!! ❤️