I have a 5month old Pomapoo. We rescued her from a friend who was unable to afford her care. She had never been to a vet so we made an appointment last Saturday and started her shots. Right after her appointment she played in the yard.. running jumping etc. The next morning she was also very playful doing much of the same. By the afternoon she was a little sluggish and we figured her shots finally took effect and she just wanted to be held. She slept most of the day. She ate and was very good about her business outside. It seems that today, Monday, she is unwilling to run and play and doesn't even walk but a few steps. We have been very careful with her as she only weighs 3lbs. I don't remember her falling or hitting anything? Could she be just sore from her shots?

Shots in humans can take a toll on them as well. Some make you sore. Some drain energy. Some do both. You might just call and mention it to the Vet.