Upset, but trying to stay calm.

Kimberlee • Mama x3 | 30 | Married ❤️
Had my ultrasound done today and she measured me at 6w3d instead of 7w5d like my app says. Doctor said she doesn't want to speak too soon and say I miscarried until we get my bloodwork back. She said it's good that the sac is growing. I'm really worried. All we saw was just a sac. No baby, nothing. I'm really, really said because I got my hopes up to see our baby. I'm praying and hoping for the best. Doctor said maybe I'm just a late bloomer. Has this happened to anyone? I'm trying not to think about miscarrying.