You give no indication of your avergae mileage a month, so there is really no way for us to try to help??? we also need to know the mileage on your first set of brakes, so we can compare.
spark plugas are due at appro 45k, it should come up for you to do in time.
FYI Brand new brake pads are like 11 or 12 mm thick.. the sensor triggers at 3 mm so maybe you can pop a wheel off and take a measure... ( its the distance from the rotor to the backing plate. dont include the backing plate)
'11 128i M-Sport Pkg, Sport Susp., 6AT w/paddles, BMW Perf CAI,Charcoal Filter Delete, BMW Perf. Big Brake Kit, BMW Perf. Exhaust, Ferodo 2500's, Titanium shims,135 trunk lip, BMS-PBX Box-Map 3, Castrol RBF600 ,e93 FSB, , f30 Backing Plates,GC Camber Plates, Hankook RS-3's (Track setup)