5W3D Sac and yolk sac on monitor, but no baby yet

I went to the hospital yesterday due to having dark brown CM. I had been spotting 4-5 days before this only on toilet paper and it was light. This looked a little worse and it scared me. They did a transvaginal ultrasound and saw a sac and yolk sac, but no baby on the monitor. The sac and my hCG levels are measuring right in with 5 weeks and a couple days give or take. Is it normal for no baby to be there yet at this time?

They said it was hard to tell one way or another and just to go to my appointment and see if my levels are progressing.

The dark brown cm has went away so far and went back to light brown. Light cramping occasionally throughout the day.

I go to my OB Tuesday for blood recheck and hopefully an ultrasound.