some of my wee bitches teets have went black ,she is feeding 5 pups, is this ok anyone know???

Perfectly normal.  I remember years ago actually trying to remove what I thought was dirty marks.  Some of my bitches, even months after pups have gone, still remain like it.

My bitch is like this now 3 months on!

Mine is like this now 7 weeks after puppies, she is losing her coat fast now too,

My girl is looking much better now! She is still on puppy food which i think has helped alot!