Hello! My rat, Schemer, has recently developed a small pimple-like growth on his muzzle. As him and his brothers are my first family of rats, i've little experience to go on as to health issues - while it looks pretty benign, I was hoping for a second opinion. The 'pimple', or whatever it may be, popped up overnight. The only signs of discomfort he's been showing have been rubbing and grooming his face more often than normal. His diet has been steady, and their bedding is changed out often, and as far as i'm aware there's nothing for him to get into, digestible or otherwise, that would be toxic - what do you all think? Thanks in advance?