Squeak Squeak

I've occasionally been hearing some squeaks coming from my room. Since it is in the garage, it isn't hard for different animals to climb under the garage door and through the door if I leave it open. I'm wondering if I have some cute little mice living somewhere in the room now. It is either that or a squeaky fan. I haven't figured out which yet. If it is mice, it will be nice to get used to having others in the room before I get married.