My dog is a Setter/Beagle mix. I noticed when I rubed his left ear he whined. I looked in his ear and there was a lot of red stuff on most of the inside of his ear and the smell was horible. I looked really bad and now no one can even touch his left ear with out whining in pain. What is wrong with him? Is it an infection or worse?

It's a yeast infection. Dogs with floppy ears are prone to this. Take him to the vet and they will clean him out and give you meds and supplies to clean his ears at home