Good call on going in later to puppy classes! That's one way round the problem.
I'd definitely stop her biting. It seems cute now but if she thinks it's fine, then you'll have a problem on your hands when she's two or three pounds heavier and with her adult teeth. The other very important thing is, it may be okay for you but she will be handled by other people including vets and children in her lifetime and you definitely do not want her using her teeth as a form of communication with other people. I don't know what the laws are in Canada, but in the UK, if a dog bites anyone - unwittingly or not - it stands a very good chance of being put down under the dangerous dogs act. For her sake, stop her biting now. Have a word with your boyfriend too and ask him to play more gently with her. If she wants to play rough, then leave her to it on her own which is what I do with Badger. If he's in a very excitable mood, I just plonk him on the floor and give him one of his 'mean' toys and let him get on with it
As for the 'affection' thing. This is the exact same problem I came onto this forum with with my Badger. I was panicking for nothing! If you look through my original posts, I was almost considering giving him back but in the last couple of weeks (so weeks 14 through 16), he has become really affectionate. He still likes to sleep on his own but he's getting closer and closer. It's just a bonding thing and takes time but she'll be a very cuddly little pup in a few weeks, believe me