My dog peeing on himself and he run to a wall ...

Change his dog food. If he is peeing on himself and seems to fall down or tries to stand up and pees on himself this could be a sign of malnutrition and his body shutting down. This happened to my dog back in January.

This could be different things. Your dog may have a serious medical condition that can be determined by his/her vet. i would make an appointment with the vet asap. It could also be that your dog is not getting enough vitamins in his/her meals. i own 3 dogs of my own and always try solving the problem at home before making an appointment but if this is something that keeps reoccurring;call the vet. You can also go to your local Petsmart and purchase a book on the breed that you own. The book is very helpful with providing medical complications and bad habits.

While I'm not a veterinarian, I'm fairly certain that the dog is showing signs of canine epilepsy and hopefully, you have already taken it to a Vet.  There are medications to lessen the symptoms, and even to stop the urinating, but there is no cure for this problem.  I wish you luck..

It could also be diabetes. My dog did this and it turned out he had diabetes.

how can he pee on him self ?

If the dog is old, it could be dementia. I have a friend who has a 15 year old Poodle, and he has severe dementia. He does not remember where to go to the bathroom and he also bumps into the walls, and goes and stands in the corner sometimes. He also has other strange behavior, like forgetting people and things like that. But, if your dog is young, then this probably isn't it. Just a thought...