Not many miles on your car Yilly, wouldn't say that you need new pads just yet, unless you are heavy on the brakes that is !, the rear off side wheel needs to be removed and the brake pads and the brake caliper needs to be inspected ( especially the caliper ) to see what is causing it to squeak, without being able to have a look myself I would only be guessing at the cause. Does it squeak when you put the hand brake on ?.
Also when you apply the brakes while driving does the car tend to pull to one side ?.