Setting aside the issue of free will, I would say that your actions are constrained by the laws of physics, not controlled by them. The actions of an inanimate object like a pen are controlled by the laws of physics--if I hold the pen out to my side and let go of it, it will fall to the ground. If I hold my arm out to my side and let go of it, I can make it do anything I want it to do, within the contraints of the laws of physics. So, instead of falling down, I can actually make my arm rise.