Agreed, It sounds like a normal GSD puppy.Awww how can something so cute be aggressive?
If you aren't use to the breed it's easy to think you might have an aggressive puppy on your hands but honest, he's just being a puppy. Lots of good threads about how to handle it all.
Agreed and Welcome!WELCOME to the wonderful world of GSD's!
Have lots of safe chew toys available and re-direct his biting to them. If he gets to ramped up his crate will be a nice place to chill out. But keep the crate a happy place to be, give him a treat when you crate him so he doesn't associate it to "punishment/time out"
http://www.germanshepherds.com/forum/puppy-behavior/85888-teaching-bite-inhibition.html a good thread to start on, then keep on reading!!