If you have taken the time to read the above sites you will notice that the owners gained their dog's trust by not taking things from them unless they gave them something even better. In the case of food, I've found that hand feeding gets the dog used to you being around the food. You are now hand feeding, so I recommend you talk softly to him when hand feeding and you might want to pet his back as well, so he gets used to you touching him when he is eating . I usually progress to putting the food in the bowl and just hold the bowl continuing to talk and pet them. Once the dog is used to this, I will put the empty bowl on the floor and put food in the bowl piece by piece if necessary, so the dog knows that I control the food, not him. Additionally, you might have some really tasty treats in hand and as you get close to the dog start dropping these so the dog is associating your with giving more tasty treats rather than just approaching his food. Once he sees that you are adding food to the bowl and not taking it away, he shouldn't feel the need to growl at you to warn you away from his food. At this point, you want to have an extra tasty treat like hot dog slices and have them in one hand to distract him from his bowl. As he takes the treats, lift a handful of food from his bowl and then put it right back. Be sure he sees you put it back. This teaches him that just because you take the food doesn't mean it isn't coming back.
I start taking food away from puppies and giving it right back when they are just puppies. If you frequently take things your pup enjoys but are dangerous like cooked bones, stinky socks, etc, without giving something better in return, you dog might think that you are planning on taking his food away. You can use the leash to provide some negative reinforcement such as a quick tug and firm low toned "NO" when he growls, but you do need some positive reinforcement when he is acting the way you want him to.
As I mentioned, it might be play behavior, but either way, you can stop that part. As far as nipping at your face and hands, this is also a pretty normal behavior for a puppy. When a dog is chewing and nipping on people the best method is to say “NO’ make a cry of pain and most puppies will respond and stop. For those that don’t respond, you will need to redirect his nipping or biting to an appropriate object. If you are playing and he nips, you want to do the same and then stop playing with him. He should learn soon that if he nips, playtime is over. Some puppies learn earlier than others and most do not totally learn not to nip and chew on you until they are 4-5 months old.
You may want to keep a leash on your puppy at all times so you can easily give a quick tug for a correction when he is doing something that is not allowed such as nipping or chewing. You also need to remember that corrections are worthless if not done when the behavior is occurring. You can only correct him when he is actually doing it.
Here are some great sites on bite inhibition.
Many puppies do not like being picked up and handled and if they were not well socialized as young pups may react a little stronger. It is actually better to not pick your pup up that much. If you need to pick up your pup, the puppy should be picked up by scooping the rear legs into one hand and supporting the chest with the other and lifting up. This keeps the pup's back in a more normal position and helps prevent problems with the discs of the back. It is better to teach them to come with you either on or off leash. Teach then early that the crate is a good place by putting their food bowl inside the crate and letting them eat in there with the door open. Once they are used to it, you can close the door. Always give a command when putting the pup in the crate and it won't be long before the pup goes in on command.
I really do doubt the dog is showing true aggression. Most likely it is puppy play behavior and just seems rough. Puppies play very rough with one another and until puppies learn bite inhibition, it can be pretty painful to us humans. I breed rotties and usually have 8 of them following me around and attached to my pant's leg. They do learn though and it usually only takes a few weeks. You can read more on this here:
I hope this information is helpful to you and you are satisfied with my response. If you would like any additional information or have more questions please don’t hesitate to press the reply to expert or continue conversation button so I can address any issues you still have .