Bicornuate uterus and 5th percentile femur length

Hi All, I went for a scan at 28 weeks and found out I had a heart shaped uterus, they weren't concerned as baby was only in the left side and right way round but now at 32 weeks baby is laying still head down but awkwardly on both sides.

Does anyone else have experience of this? They still want to go ahead with natural birth but said to come in as soon as water's break for observation just in case an emergency csection is needed.

They've also picked up that baby's femur length is short and in 5th percentile. The words down syndrome were mentioned but me and my partner didn't have any screening tests. I'm only 4ft11 myself and partner 5ft7 so he's probably just short right?

Sorry first time mum here so nervous about everything and trying not to Google 😂