How can I know if I am among those who intended an act of obedience and were rewarded for it, or among those whose setting forth God disliked, so He held them back?

One can differentiate between someone who intends to perform an act of obedience but is unable to, and someone who merely claims to, by the sincerity of their intention. For instance, the hypocrites concerning whom the noble verse was revealed: ﴿And if they had intended to go forth, they would surely have made some preparation for it; but Allah disliked their starting, so He kept them back, and it was said, "Remain with those who remain."﴾ [At-Tawbah:46], were not sincere in their intention for jihad, as evidenced by their lack of preparation for it. The verse refutes the hypocrites' claim of desiring to go forth for battle, while scholars explain their lack of preparation by the absence of any real desire to go forth in the first place. Consequently, whoever is rewarded for their intention is one who genuinely intended the action but was prevented by an excuse, whereas one who is not rewarded is not so.