Did you do your post whelp exam? They should be examined 24 hours after to check for complication (rupture, hemorrhage, torsion, prolapse ect.) and things like retained placenta or pups that can cause deadly infection and may need or benefit from an injection to help her 'clean out' a little faster (also to help prevent infection). If not you should do that and tak to them about it then. That could be minor, or could be a huge problem. Anything wrong with her, and you could lose them all very quickly. Hope she's okay.
She should not be pooping blood, check to see if you are mistaken and it is only normal drainage from the birth.