He bit me and my husband before a choke chain was ever used on him.
Hi Dac, there are all sorts of reasons as to why your dog bite you, you need to speak with a good behaviourist who has studied in updated methods and... more than likely this incident is where you became fearful and started to question all sorts of behaviour and from here the behaviours only got worse.
I have rehabilitated many large breeds, I have adopted a few who were going to be destroyed because they killed other dogs, bitten adults and children. My present dog who is one of those dogs, bite the 3 children in his home he was brought to the vet to be pts....we reconditioned his mind and now he works with my children's community programs 3 times per week. He's a star!
When you went to his bed, he was sleeping and vulnerable, and although you talked quietly he growled, he doesn't trust you
you immediately got up and backed away (correct) but he was in fear mode and in a trance like state...think about it,... if you were woken up by someone who punishes you, in a frame of mind that is condition of being afraid of his own environment 24//7/365 wouldn't it take you some time to come around from your sleep state/trance and the fear feeling? You say his growl was deep yes it was...this was his fear growl but he didn't jump forward, he stayed in his bed....he didn't want to hurt you.
His hackles were up....hackles are not always a sign of aggression, google it, it can be a sign of fear and anxiety. He paced (a sign of stress) for around for 10 mins or more in this condition....poor dog, he is so filled with fear he is anxious of what pain is coming to him.
This dog needs guidelines and love not punished for not understanding what is unacceptable in our human world. He needs proper, kind, consistent training, that will earn him rewards and praise. Dogs are the only species other than humans who can recognise facial expressions and they love to please us. When dogs are praised they will repeat the behaviour to receive attention. (This also rings true for negative as long as they get attention...dogs are sociable animals and want contact, so if your dog is doing something they want attention so how are you going to correct him what is/not acceptable, teach or punish?)
It is us who needs to understand the dog and learn dog behaviour and throw out old school thinking. Dogs are not wolves, they do not form packs, there are no alpha's and I certainly have never encountered a dog who wanted to dominate a human. A dog does what is natural to a dog we humans have to train them with patience and using our body language what we like.
And please invite him up for a cuddle.