If you're doing things 'pack style', you have to remember something very important: packs have different ranks for different members.
This is crucial to keep in mind. Your lab mix is the senior dog in the pack and I'm sure she's a little jealous of her position. From what you say, you are being very evenhanded with both dogs, and it's a bit of a (very well-meaning) mistake. You need to give her more attention than the puppy. If you want to fuss over the puppy, do it away from the older dog. When they're together act as though the older dog outranks the pup.
Secondly: has the older dog drawn blood when it growled and snapped? I doubt it. Growling and snapping are pretty normal between adult dogs and puppies, and if your older dog hasn't injured the pup yet, I doubt it's going to happen. I suspect the pup has shown submissive behavior; this is very appropriate. Keep an eye on things by all means, but if this older dog has been a good dog, I suggest you allow yourselves to trust it.
Has the pup ousted the grownup from your bedroom? I suggest you take it out of your bedroom and let the older dog back in.
I'm in a bit of a rush at the moment (heading out of my office for the day) but if I can think of any links or anything else, I'll either edit this post or else post new.
Relax! Things will be fine! It takes humor, love and time.
Nothing in the history of mankind can foul things up quicker than a computer
......with the possible exception of tequila and handguns.