Thumper has had a slight case of diarrhea for the past few days. I took away all his treats and veggies and have just been feeding him hay and water since Sunday. But he still seems to be having squishy stools. Also, he's been shaking his head more than normal (sometimes he does that as he's running) and I've seen him sleeping more than normal. I haven't noticed anything different in his personality or attitude tho. He seems happy and has been playing like normal. Should I be worried? Should I take him to a vet?