My pet guinea pig has the beginning of uri infection we have a 14 day warranty, but we don't want to lose him.?

We love the little guy and we would like to keep him. Our beloved Coco ped away a week ago and we thought we would not get another cavy, but we have a guinea pig who needs a companion. I'm hoping that they can give us the medicine and we can take him home. Has anyone had this problem? Will we be able to keep him?