Puppy Biting?

Hello again. One more question, please and thank you!
I got a new 8 week old chocolate lab on Friday. She is the sweetest, cutest baby ever. However, I think she wants to eat me. LOL! I know they play by biting with their sharp, pointy, needle teeth, but my skin just can't take it. We've tried redirection with a chew toy, and yelling "NO!" since I read that their mother and littermates would yelp when a puppy gets too rough.

It doesn't seem to really phase her at all. It may not have been long enough... but does anyone have tried-and-true methods that worked for you? How long did it take?

Thanks!