[GTP Dad]

If you just put new brakes on you either have them too tight or they are merely seating themselves to the rotors/drums. It is possible if these are discs that the calipers are sticking and there is a good possibility that the calipers will need replaced. Finally, if they are discs and didn't come with shims you should remove the pads and put some quiet stop on the back and reinstall the pads. This will elimnate the squeal that you are experiencing.

Good Luck!