Purely up to you. It is harder this time of the year but there is still a pretty good chance she will be successful if you give her chicks. If it had been a warmer part of the year the chick that fell out may have still been OK when you found it. I've seen really young chicks go through temperatures many people would have trouble believing, but there are limits.
There is a reasonable chance that hen will go broody again next year. It probably will not be early in the year and probably at an inconvenient time for you, seems to work that way a lot, but a reasonable chance.
There is a reasonable chance that hen will go broody again next year. It probably will not be early in the year and probably at an inconvenient time for you, seems to work that way a lot, but a reasonable chance.