We started to notice that our little rabbit Twilight's nose (the one we had rescued a month ago) had started to have some crust forming on it a couple of days ago. I had my brother clean it and he said that that was just the way the fur on his nose was. Well today I noticed that the crust had started to form again. Is this something that I should be super concerned about and take him to the vet right away? We're still trying to get him used to being held before we decide to bring him to a vet, so we don't want to rush him to one unless we really need to. Here's how's his nose looks: