Puppies are a lot of work just like bringing home a human baby and yours is just getting ready to hit the most troublesome stage. It will take lots of time and training to have the sweet mature Golden Retriever everyone wants. The witching hour is very common. Rukie's was at 7:30 pm and we called it hell hour. He was so wild it was both hilarious and scary. We started taking him out at 7pm and letting him run around a lot which really helped. I think there is a lot of truth to the saying that a tired puppy is a good puppy. Have you enrolled in puppy classes? They are so helpful in teaching you how to train your puppy. Try to remember that they are just acting in the way that is natural puppy behavior and your job is to teach them the right behavior to live with you. Teach a reliable sit command, it helps in a lot of situations. When you take him out keep him on a leash and running around a little so he can't eat everything he sees plus I think a little running can help them pee sooner. Throw a party with treats and praise everytime he goes. It is common to have moments of feeling like what was I thinking getting this puppy and they are often not super cuddly and sweet because they are so busy but the time passes quickly and if you teach them they learn quickly. Hang in there. It takes a lot of patience but you can teach him how to become the dog you wanted.