Hello, about 7 days ago I noticed my guinea pig started to randomly sneeze. After he sneezes I can see clear discharge but he wipes it away. It seems to happen around 3 times a day. However, his weight, appetite and behavior hasn't changed. I also listened to his breathing and it is nothing out of the ordinary, no clicking, no wheezing. His eyes and nose have no crust. It hasn't seemed to worsen since last week though. Sometimes he sneezes when I add fresh hay but sometimes he sneezes while eating pellets or just walking around. I have been worrying about him a lot. Is this normal???