I've noticed my guinea pig hasn't been eating or pooping much and she had a wet behind when i picked her up to check on her. I cleaned her up and noticed she had this spot on her underside and couldn't find anything online that looks like it, it's a brownish colored lump and at first i thought it was just a smooshed piece of poop that got stuck to her but it wouldn't come off when i cleaned the area with a rag. i'm trying to figure out how to add a photo now, but i managed to get her to drink and eat a little bit of wet food before i had to leave for work.