check your brake fluid level, or the ebrake switch, the wire could have a brake and its going right to ground or the switch itself is going bad
you may need new brakes, question do they pulsate? do u feel it in the wheel or in your ass? you may need front brakes and its hard to tell with out removing the wheel. if you do need them. use brembo rotors from tirerack.com, i got mine for 80 bucks shipped. thats more then half the price i would have payed for oem. and only use oem pads, aftermarket are crap, i dont care what anyone tells you. the rear drums normally last almost forever you are gonig to have to pull the drum and see how much pad is left. the min i would go with drums is 1.5mm if you have atleast 2 you are good, just sand down the pads surface spray the brake and drum with brake cleaner, inspect for any leaks, and re adjust and you should be good.
hope i could be some help