My cat is about 4.5 years old, male. Recently, he has had some brownish-black-snotty-booger like things come out, get stuck on and dry up, right on the outside of his nostrils. Also, sometimes, he breathes like he has a stuffed nose. However, it doesn't seem to be like a cold cause these breathing episodes last for less than a minute, usually after he wakes up, or is nervous about something (like someone petting him, when he is not in the "mood", or just general extra commotion). Everything else is fine though, he is energetic, eats (wet and dry), drinks, litter box stuff, all perfect. (He vomints like once or twice a month, but I don't think its related). Should this be cause for concern?