Without being able to see your dog in person, it's almost impossible to tell you what that hole in your dog's side could be.
My first two thoughts would be either injury of some kind, or some sort of growth that broke open and is bleeding.
The only way to know for sure is to have a vet take a peek at it. However, you can avoid spending so much money at the emergency clinic, and wait until Monday when your regular vet is in the office.
In the meantime, while you wait for the vet's office to open, you can keep the area clean with some warm water and a gentle soap cleansing. You can also use a little Neosporin on the area to help inhibit bacterial growth on the site.
Of course, if your dog becomes lethargic, has vomiting or diarrhea or stops eating, you should have him seen, just to be on the safe side.
I hope this helps.
Thank you so much. I feel much better about it. I love this dog as much as if he were a child! I am on a budget so cant' afford an emergency clinic. I will wait until Monday and get him in first thing.
Thank you very, very much!
Lora Mullen and Harley