Hi all, Thank you so much for your support and kind words so far. I was going to open a new thread, but since the topic is still the same I think it makes more sense for me to write here. In the last two days Gerry had been better. Today I took him upstairs as I was going to iron. He started to scream non-stop (obviously), I must have walked out of the room 20 times, waited for him to stop, then walk back in. Nothing, he never got the slightest hint of why I was walking out.
After an hour of solid screaming and me starting losing it and thinking I wanted to kill him, I started to use a spray bottle to his face every time he started. It seemed to have worked although obviously tomorrow he will start screaming again. I know this is punishing and I don't think it's a nice solution, but God it worked, for once one thing made him stop for a minute.
One thing I noticed is that he seemed aggravated by me ironing, the clothe movement or something seemed to make him stressed out. A couple of times he jumped on my head, but it was not the nice "I want to perch on you or preen on you" that he does at times, he bit my head, which made me honestly hate him so much. Note: the jumping on my head was before I started using the spray bottle, so it was not caused by me using it.
Do you know why the ironing may have aggravated him and do you know if using a spray bottle consistently could be a good option? I never used it before but today I decided enough was enough.
Just going to pick up on what you said here.
Interesting about him being aggravated by your ironing. This is information. It wasn't successful so I wouldn't try it again. Bobbie (Red-lored Amazon) really doesn't like cloths/kitchen towels/tissues waved near her. She also becomes aggressive. So I just make sure never to have anything like that in my hands when I go close to her. But it was good that you tried.
When
doesn't he scream? What is he doing then? What are you doing? What was different/successful in the two "good" days you just had with him? See if you can build on those times. As has been said there will be good and bad days. He's been screaming like this for a long time, so it's going to take time to learn to do something different.
I started to use a spray bottle to his face every time he started... for once one thing made him stop for a minute.
As you noted, punishment usually only works short term, because it is not teaching the bird what to do instead. Plus you are going to be associated with the punishment, so trust levels will fall. There are other side effects to punishment which are, depending on the character of the bird, increased aggression, or increased fear to the point of phobia. If you can catch a "good" behaviour much better to reinforce that instead.
If he doesn't like showers, try pointing the spray bottle into the air on a very fine mist setting and letting the mist fall gently back down on him. Gradually as he accepts that, you can start spraying him gently directly. Having the vacuum cleaner running in the background often gets a bird in the mood for a shower. It certainly works for Bobbie and Kobe here.
As well as trick training, why not teach him to play on his own by praising/encouraging any movement towards a toy or other object that might be interesting for him. If he learns to play with toys on his own, it is something to do instead of screaming. You could teach him to destroy toys rather than rip your sofa to shreds. Re the sofa, try covering the areas he chews with towels/drying up cloths as either a protector or deterrent. I have towels over my book shelves and cupboard tops. My sofa is covered in a throw with added kitchen towels along the back and arms.
Thinking of his chewing, has he got natural perches in his cage that he could chew? Maybe apple branches or willow if you have access to them. Maybe give him an empty food dish full of chewable foot toys. All my birds love these. Here are some ideas:
We offer a selection of parrot foot toys, safe parrot toys, parrot enrichment toys
www.naturalbirdco.co.uk
Most toys you buy for parrots are made of hard wood and so difficult to destroy. Try stringing some easily destroyed materials together, like cardboard, pinewood, balsa wood, leather pieces etc. There are lots of toy ideas on the Natural Bird Company above and they sell toy parts which is useful.
With Ollie (Orange-winged Amazon) who was afraid of toys, I started off with budgie sized easily destroyed toys I made myself - plain to start with, then I gradually made bigger toys and began to add colour. It is important that they are rediculously easy to destroy at the beginning to get them going. Then you can gradually add harder materials, but never too hard that they lose interest.
you need to try channel his energy into something else. 
