Guessing you're talking about nofap? Well either way, whatever sin you're talking about, it's just one fall, get up and try again, work your resistance to impulse like a muscle, it's rough for everyone, just don't give up and don't think he wants you to give up either.
Your goal right now is not to let it effect the rest of your day, move ahead and get your feet in motion, apply your hands to something noble and useful, with him in mind always, ask him for the strength, pray constantly.