S.W.
C.,
If you have found good care for her and you can be comfortable with your decisions, your daughter will be fine. I started my son in daycare at 9 1/2 weeks. He is now almost 8 months old and doing well. I started my daughter at 14 weeks. She is now 4 and is also doing well.
With my son, it was hard to leave him the first day or 2 and then easier after that. With my daughter, it wasn't hard at first because I liked my job then and was not very comfortable with being a Mom (the reverse of now). There will always be times that it is a little harder to leave her esp. when she is a little sick but not sick enough to stay home, or tired and you wish you didn't have to wake her and drag her out of the house or if she is uneasy because of a substitute teacher/ caregiver. But you just get through those days, as best you can.
If possible, you may want to do only part-time the first week or two, to help you adjust.
I hope it goes well.
Best Wishes,
S.