Looking for remedy for my dog

I am looking for treatment for my dog.
Overall set of problems:
1. Itching all over
2. Slightly twisted knee on back left leg though not visible complaint when he walks
3. Sensitive stomach/digestive system
4. Thirst levels are low
5. Tends to overweight
6. After the vaccination, he is shaking his left back leg when he starts to walk. It is not often, but I have seen it a few times.

Following are the details as much as possible I could put:

Breed: Golden Doodle, Weight: 58.4 pounds, Build: 18 inches height, medium build, about 2 months back, I found one of the molar of right ride was bleeding. I cleaned the area and then gave him Merc Sol 30 one dose, which cleared out the bleeding. I

He itches a lot, especially when he is inside the house. He usually itches near his armpits, but also itches near his ears, on his head or under his jaw. This is really troublesome for me. I spoke with the vet and did all tests related to worms and allergies, but nothing came out. He also licks his chest area and paws. Also, I observed that during early morning hours, while he is lying down, he usually moves his tongue as if someone is thirsty and moves the tongue all around as if trying to lick around.

As of couple of weeks back, he had a few black color bumps on his head. These were similar to the clots that formed when the wound starts to heal. However, I didnt remember him getting any wound. In addition, he has started to itch that area. Soon, those black clots went away.

Cody seems sensitive to cold weather and we have observed that during that weather, if he is exposed more, leads to diarrhea. Also, before I observed the bumps, he had diarrhea as well, which I tried giving him Dulcamara 30c, which kind of helped him. Overall, I feel his digestive system is sensitive as small variation in food may cause diarrhea. So, we are scared of trying something different.

One more thing, we usually keep Cody without leash when inside the house. We have never put a collar around his neck. So, when we get him ready for going outside and put leash on him, he stops itching and calm down, not matter whats the situation.

He is up to date on his vaccinations, however, I have a doubt that the current itching might be because of his vaccinations but for that I dont know which medicine to give. His teeth have plaque as well.

He pants when the temperature goes high and usually doesnt go for walks. He also avoids going in rain as well when it starts to become moderate. He likes to play in sand and starts digging it with his front feet. When there are firecrackers outside during July 4th, he started barking. Regarding travel, he likes to travel in the car, rather Id say he is fond of traveling in the car.

As I mentioned, he gets scared when we increase tone of our speaking. I have observed, a few times that he walked as if he was going to vomit - mouth downward and walking. A few minutes later he was fine.

He doesnt like fruits. We feed him boiled vegetables and organic chicken breast.

He is more playful and yielding in nature for humans. However, for a few dogs around the house, whenever they pass, he barks alot to them. These are the dogs where one of them attacked him about 2 years back when Cody was 2 years old.
Cody is usually not interested in playing with small dogs. In fact, he runs away from them. However, with dogs of his size or larger, he likes to play with them.
He is overall a good dog. He gets scared when my wife or I increase volume on my sound and tries to hide away. He is scared of closed spaces and is scared of going into the elevators.

He is a well mannered dog since the beginning. So, we never felt need for training him. Also, we never felt him being aggressive with other dogs.

I had a visit to his vet on Jan 22nd 2025. Upon examination, the vet told us that is knee joint is not correctly aligned. Though we have not seen him limping, but we have been told to keep an eye on it. I am little worried about this as he hasnt had any injury that healed to that situation and may have been before we brought him home. He is advised to take calcium supplements and omega 3 liquid. He also has sensitive stomach. His poop color varies from green to light brown. When it is green, it is outside shell that is green and from the inside it is yellow.