Alot of brake pads have a "bedding in" part to them. The first 2-300 miles wears this away and they do tend to shed alot of brake dust during this time. It could either be that, or the backplate could be touching the disc, causing a squeak.

Jack it up and spin the wheel round, you'll soon find the issue.
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K&N, 35mm droper, axle spacers, de-tango, LED's all round, Retro Fiesta badge, wind deflectors.