What does the bird look like? The best thing would have been to find the nest it fell out of or find a safe place nearby in the barn, because the mother would most likely find it and take care of it there. Does it have most of its feathers or is it real young looking?
Not many baby birds live when people take them in. A kind heart and worms isn't enough usualy. You would need to know what type of bird it is to know what to feed it. I would take it to a wildlife rehab place to get tips on care. Good luck, I hope it survives.