Why is other dogs urine scent bothering my dog so much?

I would also recommend treating all the spots the other dog went with an odor neutralizer. A dog's sense of smell is a lot sharper than a human's. I've seen Nature's Miracle recommended by a lot of people. Odo-Ban is good, if you can find it.

Hopefully his apprehension will disappear after a while. However if it doesn't you are going to need to do some training such as luring him into the house with treats and giving him a lot of good things in the house so that he knows this is still his safe spot.

When a dog pees and poops like you described, he/she is usually marking their territory/ claiming new territory as their own. Unfortunately, if your dog is now unwilling to enter your home, it typically means your dog accepted the other dog as the alpha. This means your dog sees your home as the other dogs territory. Removing that dogs mark is the most important step, but it isn't always the easiest. I would have to agree with Shannon about the Odo-ban. I work at a pet boarding center, and we use it all the time. If you use it, try the lavender scent. It will help ease his anxiety about the situation. As well, Febby was right with the treats. You want him to feel comfortable and secure in your home, otherwise he may not get over this.

Best of luck!

The only time a dog will pee multiple times somewhere is if they're marking their territory. Your dog is smart and is not trying to invade another dog's area.

Another smell get er outter is covering with vinegar then baking soda. Let sit minute and then vacuum up. Then I'd clean with the other recommend cleaners. And its very important your cleaner doesn't have ammonia in it cuz thats the same ingredient in pee!