My guinea pig 2 or 3 days ago started acting abnormal. He is always the one to come running to the hutch door and almost falling out while begging for food. He is also the more hungry one and usually spends more time eating than his brother. Recently he's had less enthusiasm to eat and doesn't do his usual stuff. Yesterday evening I did see him eating hay and drinking water and the same thing today. But he just doesn't want to leave his hutch and run around the garden with his brother. My mum noticed that all he does is go behind the hutch and sit there and just not move around much if he was put outside. I picked him up today to see if I could see anything that was out of the ordinary but he just looked the same to me. I'm not sure if it's just me but I thought he seemed a little lighter than before and I think this may be due to him not eating his veggies as much as before. He only took nibbles from the pepper I gave him this morning and refused the kale. I think his fur may have looked slightly drier/more scruffy? He's also not old, born in June 2017.