I had a vaginal ultrasound today. in the ultrasound one picture shows a good size lump beside the baby aginsted the wall of the placenta. in all the other pictures there is a small circle beside child?

Without the image. .: It's hard to know what you are describing without the image, but it sounds like a placental chorioangioma, which is usually a benign finding. Google that, and look at "images" to see how it compares to what you've got. By the way, the small circle is the yolk sac.

Ultrasound vaginal: You have to be a professional to interpret ultrasounds. Ask your doctor about the meaning of the ultrasounds.