If you got your puppy early at 5.5 weeks, as you said, it's possible your pup didn't learn enough about bite inhibition from his littermates. Generally the time between 4-7/8 weeks is considered an important time for socialization for littermates (this can also be a problem also if there is only one pup in a litter). In this time, puppies bite eachother in play, and learn (when their brothers and sisters yelp in pain) how hard is TOO hard to bite. I would speak with a good trainer, try to find some good articles by searching for "bite inhibition", and remember that you do have a puppy.
Rolling a young pup on it's back (alpha rolling) can have some bad effects on the puppy mentally...again, find a good trainer. Like Rona said, wolfdogs can seem...emm, crazy, deaf, defiant...and then one day, the "storm is over". Good luck!