How old is your dog?
What breed is your dog?
Are you giving her any medication on a regular basis?
Have you changed her food recently?
Has she sustained any significant injuries recently?
The more information you can give about your dog, the better we can try and help you.
I have a red-doberman that had a very dark brown nose when she was younger. Over the years, her nose has metamorphosed into more of a pinkish-red color.
Answer some of the above questions and we might be able to help you better.
Hello myoung304,
Sometimes a dog's nose will change color. This can be caused by having your dog eat or drink from a plastic dish. There is a reaction with a substance in the plastic which causes color change. Stainless steel bowls for food and water are highly recommended. Other causes of color change are vitaligo (loss of skin pigment) and cold weather. Color usually goes back to normal in warmer climate. This is usually no reason for concern.
For more information, check out this website:
http://www.happyk-9.com/dog-nose.html
Good luck!