There is never really a scheduled service for brakes because they're so many variables.
A lot of it depends on driving style, I have known people who go through front pads in one year and others who have them last 5 years and 35,000 miles.
Some cars also have reputations for eating up rear brakes, but that is very out of the ordinary because usually the rear brakes will last twice as long as the fronts since the fronts are doing the vast majority of the work when you are braking.
All I can say is, you should visually inspect your brakes. You should be able to see how much pad is left. If it looks good and you have no other issues such as vibrations under heavy braking then it should be fine. You can also take a caliper and measure the disks if you wish, there is usually a recommended window for the thickness.