It's pretty common to read posts from people who are frustrated and stressed! You're not alone!
You already know 6 weeks was too early to leave mama. What this means is the little guy is missing out on learning puppy manners and bite inhibition from mama and siblings. So, you have to take care of this!
Very young puppies like this are not really "aggressive". BUT, they do have a lot of behaviors that people can misinterpret as aggression. In reality, it's a puppy that hasn't learned manners yet.
Growling is the only way dogs can communicate with us, since they don't have words to use. Growling can let you know something hurt them, or they are scared or uncomfortable. Once, when petting one of my dogs, she growled as I pet her "arm pit" area. When I checked it out, she had a pretty bad scratch that wasn't in plain sight. Growling can also let you know something makes them uncomfortable.
Then, there's also the play growl, you will learn the difference as you get to know your puppy better.
Puppies bite and snap as a form of play, it's how they explore their world. It's kind of like the way a toddler puts everything in their mouth. Check out the sticky "The Bite Stops Here." It's great! A word of advice: be super consistent, and don't give up. Many people think teaching a puppy not to bite all the time should happen quicker. So, they give up on one method and try something else. All that does is confuse the puppy. Remember, you're not just trying to stop the biting on that one occasion, you're trying to teach something that will stay with the puppy for the rest of his life. So, keep doing the same thing every time he bites.
Basically, when the pup bites, you make a noise, like a yelp, or saying OUCH loudly, but not angrily. Whatever you choose, stick with the same noise hereafter. The noise is to let the puppy know you didn't like it. The pup will probably go right back to biting, as it's what they do. Make the noise again, but this time leave the room for 20-30 seconds.
This is what you would do EVERY time. Yes, it's a hassle to leave the room all the time, but it will work.
Good luck!
