My kitten is 9-weeks-old. We got her on Monday and on Friday she went to the vets to be vaccinated and de-wormed. Before this vet visit, she was playing all the time, full of energy, eating etc. Now she just spends all day sleeping on the sofa and doesn't really play or eat her food. Is this normal? She still interacts with us but there has been a remarkable change in personality the past two days.