My Jack Russell is 9. He's usually very sociable and comes to sit in whatever room we're in and is very affectionate. For the past few days however he's been laying in his bed/hiding in different places and behaving very out of character. He had some booster jabs a fortnight ago - unsure if this could be connected? I've felt him all over and nowhere seems to be tender. He's eating and drinking fine but hasn't bothered sitting under the table to catch kids dropped food as he usually does. He has a vet appointment on Friday but does anyone have ideas in the meantime? He growled earlier when I accidentally knocked him with a toy which is extremely out of character and worries me that he's in pain.