I just went out to do my evening feeding and my mare (9 years old) had a trickle of blood coming from her left nostril. I cleaned it out and couldn't see any cuts or anything, seemed like it was coming from deeper within. She was ridden yesterday and not today at all and from what I can tell (based on the amount of blood), it lasted about 15 minutes (it seems like it's stopping now). I've had her for 2 years and this is the first one she's had. I tried calling my vet and their answering service asked me if it was a "dire emergency". I said I didn't think so but I didn't know for sure as I've never had a horse with a nose bleed before. Any thoughts? Should I get the vet out for an emergency call or wait?