Wildlife on One

I don't know whether I've still got mice at home. I don't see them anymore, nor do I hear them. I haven't found any 'evidence' of them either. When I think logically about it, I can't see them moving out when they've taken the trouble to move in. I've done something drastic and bought some mouse-traps. I really didn't want to do that, but I need to do something, as I'm not allowed to have pets in the flat.