Baby not growing?

I had my first ultrasound on Monday 10/14 and I started bleeding on Friday 10/18 from a subchronic hemorrhage. So I had another ultrasound done. My baby still had a heart beat, but baby has not grown in size since Monday. Should I be concerned? I know it’s only a four day difference, but shouldn’t baby at least be growing a little? I have a 2 week follow up ultrasound, but can not stop worrying about it. 😞