Welcome to the world of GSD puppies..LOL My legs, ankles, arms, have the scars to prove it. When mine did this, I would shove a toy in her mouth to redirect her away from me...if they are busy chewing something else there not chewing on you..LOL I could not walk across the room without my pants leg being attacked. Those little needle teeth hurt, mine stopped biting around 6-7 months, Hang in there, this to shall pass.