Is there a spirit in my house?

I'm 13, and I have 2 dogs. just right now one of my dogs just got up and just stared at nothing up and down, and then she followed whatever it was with her face and i guess it was going my direction, because she growled at nothing. She never does that. and then i felt something cold and then back to the original temp. again. I have two urns in my house. My uncle who died when i was 4, and my grandpa who died last christmas eve. do you think one of them might be lingering? they werent evil either