Angel between

I must not understand something fundamental because I'm confused by what should be easy. I want to push a sprite in the opposite direction of where I click, but for simplicity, let's say it'll go in the same direction. Here is what I do:

%mousePos = $TheSelector.getPosition(); // sprite that's locked to the mouse
%myPos = %this.owner.getPosition();

%angle = t2dAngleBetween(%mousePos, %myPos);

%this.owner.setImpulseForcePolar(%angle, 50);

The values for '%angle' seem completely about distance, not angle.