The day my puppy (now 11 weeks old) came home, was the day we started training. My pockets were always loaded with tiny treats (about the size of a Cheerio), and we just worked on commands throughout the day. A sit here, a down there. We worked on Come a lot, but in little bits. I'd run; she'd run after me; I'd gleefully proclaim her name (learning her name is a big training goal), then the word Come. When she got to me, she got her treat and a wonderful rub down.
Within a few days, she had Down, Come and Sit pretty well down. Then she figured that if she Came and Sat right in front of me together, I would be really impressed and the treat was twice as good. We're working on Wait (which will become a hard Stay over time). She's learning to Shake. And since she likes to bark a staccato bark when she gets excited, I'm working that into a nice Speak.
Uh-uh (actually a fast unemotional uh-uh-uh-uh!) means stop what you're doing and look at me. And "Leave Zamboni" (my older dog) means go find Camper (I"ll call him over) and play with him instead, or find something more constructive to do (I'll offer a toy, or I'll take off running so she can chase me), or play time is over. She's still working on that command. But she's getting it faster than you might think. Time outs often work well with rambunctious puppies!
I try hard not to even use the word No with puppies. We fall into that trap early. Then everything becomes No, and puppy doesn't know what she CAN do. (One of my trainers once explained it this way: if you walk into a room, and every time you tried to sit somewhere, the host said, "Don't sit there." But they never said where you could sit, you'd get really frustrated, right?) So, our job, as "host" to our new family member is to show them what IS acceptable behavior, not to constantly tell them what they should not be doing. Make sense?
One more thing. Watch your lab closely. Is your lab really well socialized? If your lab is well socialized (and not older and/or in pain), it's *possible* that your lab isn't "biting". My GSD will literally take my puppy's head into her mouth. The whole head. They kind of look like the old circus "now watch me put my head into the lion's mouth" act. It's terrifying to watch. But his mouth is so soft and she is not afraid. He is not being aggressive. It's what they do. When she finally antagonizes him to the point that he's really bugged, he'll do the same thing (as she rolls on her back in submission), but he's still not biting her. He's just making a point about dominance, and her role at the bottom of the pack.
I guess the question is, what's your role in the pack? Are you the unquestioned leader? If not, start NILIF now. (You can do a search of that term on this forum for lots of details). It's a great way to manage one dog, much less a pack of them. If you are, then your lab likely accepts your bringing in this annoying puppy. Does he, overall, like the puppy? If so, he's handling the puppy, when she gets annoying, his way. Yes, you absolutely need to stay on top of them. But watch and learn. Dogs communicate in mysterious and wonderful ways. My older dog sounds like she's going to rip the puppy's head off when the pup bugs her. But she's gentle with them, her tail is wagging, and well, I've brought home enough pups and young dogs to Zamboni that I know this is just a game she likes to play. She's the alpha and she likes to make sure the kids don't get too rough. They learn how to be polite dogs from her.
So while I'm training Sits and Downs, she's training even more important social skills. I couldn't raise young dogs without her!