BLOOD POCKET?

I went for my first appt and they did the ultrasound I'm 7w6days today. They told me there was a pocket of blood above the placenta anyone ever had this? They said it could reabsorb into my body or it would come out but it should be dark and if it's not it's an issue. I'm so worried. I don't want anything to happen:( you can't see it in the pic. Just wanted to share! Baby looked great and heart rate was great. 144 BPM. I'm just stressed out I've had two previous pregnancies and nothing like this.