Between decision and decision

The most recent is in the Science of Freedom, p. 400:

I think people may confuse the feeling that I have decided with the feeling that I have decided. Before pressing the button in the Libet experiment, a person has a feeling that he has decided, but not necessarily a feeling that he has decided. "Decision" can also be a mental expression of nervous excitation, but "decision" is something that should be carried out in our consciousness and stem from a process of consideration. The question is whether this is an illusion of choice or a (non-illusory) feeling of decision. It is important to distinguish between the two.

I didn't understand the difference between a decision and a determination.