You didn't say what type of bike and brakes you have. Sometimes the brakes get nudged out of place. Try putting the wheel on, spin the wheel and see which brake is rubbing. Then just grasp the entire brake and gently move it till you have equal space on both sides of the rim.
Sorry about the lack of info. Disc breaks on a fuji tread (kind of a path/road bike). From what I can tell, it's not the breaks that's dragging. It feels like it's the placement in the axle. I'll tinker around with it today.