This question is rather self explanatory so I'll keep I succynct.
A while back Tim Peake photographed a small crack in the cupola of the ISS, which was reportably a paint fleck that collided with the window. According to orbital mechanics (Kepler's Laws I believe specifically) the higher the velocity the larger the radius, and therefore orbital period etc.
How does a paint fleck damage the ISS when it would have to be travelling at a significant (enough to damage the window) relative velocity to the ISS, and therefore a higher velocity, so surely the orbit would be higher than the ISS's orbit and therefore the collision could not occur?