HELP PLEASE!!!

Dakota
So I had my first ultrasound yesterday. I was supposed to be 7 weeks, 1 day. But when she saw the baby she said it was only measuring 5 weeks and something days (I don't really remember.) And that the sac is measuring 6 weeks, 1 day. We couldn't see a heart beat and she said its either too early or the baby stopped growing. My LMP was 12/24 and I got my positive test on 1/28. Maybe I could've ovulated later? I'm not sure when I ovulated at all. Anyone else experience this with a positive outcome? I haven't had any cramps or spotting etc. I don't want to worry but I want the baby to be okay and don't have anyone to talk to about it. 😢💔