My family adopted a stray kitten about six months ago, named Sam. He is typically loving and enjoys being around the family - he has an excellent temperament. This morning, he was doing fine - playful and loving, eating normally. However, this afternoon when my 11 year old picked him up, he cried loudly and started hissing - this is not normal behavior. I walked over to pick up Sam to see what was going on, and he did the same to me. As he laid on the ground, I started to rub him to calm him down and as I rubbed down his back along his spine, about mid-way down, he started to cry loudly again. The only thing that is different than the norm was that he snuck out of the house last night, so I was concerned that he may have gotten into some trouble. However, again, he was perfectly fine this morning and was until early afternoon. I've also noticed that he isn't using the litter box or eating, so maybe constipation. I called the vet, and they can't see him until tomorrow afternoon, so of course, being a new kitty mom, I'm nervous and not sure if I should bring him the emergency vet or just wait.