GreekMaxima

i was driving in the heavy rain tonight and went about 70 mph, i step my brakes and i heared "voummm" very heavy sound from my brakes... no shake, no nothing, just a "voummmm" something like that. I need pads or rotors?
Da** i changed them about 5 months ago... or maybe the sound came cuz was rainning? usually i dont have any sound from my brakes when its rainning... any help guys?

thanks a lot!