Since your doing mostly city driving, I think it is reasonable to assume its about time to change the pads.
These cars are heavy and the front pads wear down faster than other cars.
I drive mostly freeway and I get about 25k-30k on a set of pads.
My rear pads are still original after 147,000 + miles.

Also the rotors wear down pretty fast on these cars too.
I change them about every other pad replacement (about 60K miles)