As she had dead lambs inside I'd give her a shot of Pen & Strep. And Combivit too, if you have it.
If the placenta doesn't come away in the next couple of days, you may need the vet to help. And if she is anything other than bright and happy, and feeding and drinking well, herself, also get her to the vet.
But yes, if you are at all unsure, have a chat with the vet over the phone.