First off, glad you're okay. Any encounter with the pavement that's enough to chew up your steed's metal is generally enough to chew you up too. So primum prima, it is good that a fellow BF rider escaped unscathed.

Second, sounds like you've just christened your first pair of training wheels (race training, not "stay upright" training).

The advice you've gotten on sanding them down is sound. If you take care of your rig it will take care of you.

Third, check to ensure that the wreck did not knock the wheel out of true. Spin the wheel with your hand and ensure that the rim has no left/right wobble relative to the brake pads, when viewed from above.

Next, check to ensure that the wheel is not out of round. Spin the wheel again and view it from the side. Does the rim stay the same radius from the hub at all points? You're good to go.

Rock on man.