This is an old post so I don't know if anyone's reading it anymore, but I understand having the question. The other day my cat had a bloody nose. I don't want to take him to the vet for a bloody nose - at least not until I know a little more about it. This is a good site to get some immediate information on what a bloody nose might mean (it turned out to be a boo-boo inflicted by his little sister).
If I had called my vet, I am 100% sure that they would have said they would want to see him to make a diagnosis. They're professionals and they have to cover themselves. Just think if the vet says "Oh, a bloody nose is no big deal. See if it goes away and call me tomorrow." and then something dreadful happened.
Storm (beeps and has a pink nose and toes),
Misty (with big blue eyes and tasseled ears),
Anya (only ever called Honey - she's that sweet),
Zander (who goes by Punkin' cause he's almost that bright)
Kasee (couch potato who thinks she's a dog)