Can't see baby because of placenta?

Jenna • I am a stay at home mom to 1 boy (13) and 4 girls (11,8,5 and 3) we lost another little girl last year and just got a bfp for our 🌈 baby!
I went in last fri at 16 weeks for an ultrasound and we were barely able to see baby. One leg, and top of head were the only parts we could see. She said everywhere she looked it was just placenta in the way. This is my 5th pregnancy and I've never heard of this. Anyone have a similar us? I'm just worried something is wrong.