Dog breathing heavily, increase thirst, red bump?

I have a 4yo male Old English Sheepdog who is neutered and trimmed (2-3inches of hair). Bentley is an indoor dog and stays outside 8 hrs a day while I am at work. About a week ago a raised red spot the size of a pea appeared under his nose, it is not sensitive to my touch. All of last night he was breathing very heavily and had a significant increase in thirst. It has been in the low 70's outside and I keep the house at 72degrees. Could these symptoms be related to the bump under his nose?