S.W.
I would much rather know that it is not a good fit with my kid then you continue to watch the child and not be happy with the situation. So just be honest and don't feel bad!! when you see her tomorrow just speak up and let her know then(don't drag it out)tell her, you thought it would be a good idea to have the infant, but infants are a lot of work and responsibility and you have come to realize that as much as you love her precious baby that you realized that you are pass the baby stage. Give her about a month or so to find a new provider(you don't want to give her much more time because if you are already ready to be done, even a month is a long time!!