anatomy scan - breech and venous/placental lake

So I had my anatomy ultrasound today. Everything seemed to be good except for a few little things... they said he is breech, but also said that could change by the end. Has anyone in this group had a baby be breech at 20 weeks (in previous pregnancies), and what was the outcome? Also, I have to go back in for another ultrasound in 4 weeks to check his growth. I guess there is a small placental/venous lake near (but not covering) the umbilical cord and they want to make sure it isn't effecting his growth. I'm trying not to worry since the doctor said that it's a small and pathetic reason to call someone back, and just to see it as a bonus ultrasound. Anyone else experience this and have some words of wisdom?