could be the front pads, could be the rear. Check the front first. Probably will need to replace the sensor also. Not difficult jobs, either one.
1995 325I, window tint, K&N, debaffled airbox, BMW #104 wheels, Nighthawk low beams, smoked side markers, smoked corners, smoked taillights, M3 stlye heated mirrors, various interior bits, Bosal cat-back.