Brake and ABS light comes on on 2000 BMW 323i

New brakes and rotors done, and brake light and ABS light comes on and stay on for a while, then goes off. Also felt something moving/shifting while foot on the brakes.

3 answers
wheel speed sensor. for the price of 3, about $90 you can also have it put on the computer to read which wheel sensor is bad...this costs $95. So buy two, change out the fronts, if the lights don't go out, change out the rear. Easy job, all you need is an allen key.
This needs to go back to the shop that performed the work, and you may want to tow it, this sounds dangerous.
I heard it could be speed sensors