It's hard to say what that could be; anything from ringworm, to a simple scraped up nose. Only your vet will be able to tell you for sure.

When Dusty showed up her nose was way worse than the pix you posted and her only problem was an upper resperatory infection.

Make an appt. with your vet so you don't worry yourself over something that may be a simple answer, or to the other extreme of letting something go that's best dealt with now.

Good luck