Yup you should be seeing small pill shaped droppings. Mice leave them everywhere (if you have them).
A cheap solution is to ask a neighbor with cats for some leftover litter (urine litter not cat poop). Fill up a small disposable tray or bowl with the urine soaked litter and put it up in your attic for a few days. I’ve had mice clear out the day of and never return. Also consider just getting a cat for long term pest control.