yeah the first thing i would check would be the "squealer"
in addition, excessive brake dust can cause harmonic resonance and make a squeeky squeely sound.
if you just replaced your brakes i would dissassemble them (only disc's not drums) and put anti seize on the slides for the caliper and clean all of the brake dust off that you can see.
also there is a gel that you put BEHIND the brake pads that will absorb some of the harmonics
hope this helps