Date off by almost 3 weeks???

Mattie β€’ Married to the love of my life. Mother to sweet baby boy - 27 months. Pregnant with baby boy #2!
So I had my first ultra sound and thought I was around 9 weeks (my periods haven't been regular since I had my first child 16 months ago) but the dr said I was measuring around 6 - 7 weeks. I have to go back for another ultra sound in a few days, but I can't help but worry! 😒😒😒 I felt like it took a while to start getting symtoms, then all the sudden they hit me hard, now I feel like the last few days they have gone again! And have had very moderate cramping and zero bleeding. Do miscarriages always have to have heavy cramping or bleeding? Has this happened to any of you? All prayers currently being accepted! πŸ™πŸΌπŸ™πŸΌπŸ™πŸΌπŸ™πŸΌ thank you!