I found mice droppings?

My house is really clean but I found mice droppings in my spare room under the fitted sheet on the mattress and in my bedroom on my night stand....ewww i'm freaked out....how do they get this high????? What is the best way to get rid of them? I have 2 dogs that get everywhere so I'm a little hesitant to get traps....what should I do/?? Please any help is appreciated I have never had mice before and I am freaked out