A lot of babies have the cord wrapped around them, its normal, they usually unwrap themselves. Also, a lot of babies are born with the cord around their neck and they're just fine. So don't stress it too much.
What does it mean when the placenta is implanted on a sheet? I've never heard this before, i'm curious. I hope that something can be done so that the cord doesn't remain wrapped... My sister came out blue because of that.