Slapping the backboard

[JWC]

Player A is driving to the basket and shoots a layup. Player B slaps the backboard hard. This guy can realy jump. I signal a "T" for slapping the backboard. About the time I do this the ball rolls around the rim and goes in the basket. Well now what do I do? I counted the basket and we administered the Technical (shot 2 free throws and gave team A the ball at half court. My partner disagreed.
Did I get it right? If I didn't at least no one slapped the backboard again that game.

jwc