[HighlandYorkies]

I would deffo say the right way to go is neutering...but wait till he's a few weeks older. He is showing all the signs of being a male stud dog...marking, barking, growling, etc.
He is obviously being more than just a hyper puppy or you wouldn't be so worried.
You are doing the perfect thing getting him properly trained....it all takes time.....and I would enlist your vet's advice in enlisting a behavioural therapist for the biting if that is definately not teething related, as that could be his worst issue, especially along with the growling.
Are you sure it's not him just being a boisterous puppy ?
He will have very sore gums just now, so will try to chew things like your hands...get him a few good dog toys...the growling might be just a play thing to him, but you are right not to encourage that....if he goes for your hand...give him a toy instead.
Try getting him used to being touched gently....could you use a brush or your hand and just gently touch and stroke him all over on a frequent basis...take your hand away if he goes to bite you, then try again, slowly and gently so he doesn't see you as a threat.
Keep putting him out to pee....Yorkies sometimes take a long time - even over a year to be totally toilet trained....it's just perseverance and praise when he does it correctly. Use a word like "go potty" "do peepees" and heap praise on him when he does as he is asked...he will soon pick it up. The main problem I find is knowing when they are asking to go out...some aren't very good at letting you know !
Never scold accidents.....praise him doing right.
Check out his food for additives that might be disagreeing with him - you could try a more natural food which might make him less aggressive...the vet will advise on this too.
Take him on lots of walks, and don't leave him alone for long periods...take him with you, or have someone check on him until he is older.
Tell your Mom that you got the dog and will do your best by him, and that is NOT giving him up to some stranger or dog-pound.....get a good Yorkie book and take it from there.....it will give you loads of tips and facts.
You are doing right not letting little kids play with him...avoid them if they are rough...but you must continue to take him as many places as you can to get him socialised so he is not scared of things.
He is young and will be a rascal for a few months yet...it takes time to get the dog you want....some of it is just puppy behaviour, but your vet will put your mind at rest over issues that are worrying you, and give him until he is 18 months old, with his training and love from you, he will come good.
They get more sense by 18 months !
Remember to get him neutered at 5-6 months...that will calm him down a bit.

Plenty people on here will help you...don't be frightened to ask for help
Keep us posted !
Debra