Talk to yourself -- a lot. Really. Do what you need to do to be as positive & excited as possible -- leave the tension & negativity out of your voice. Be excited! What a great opportunity for your daughter to be surrounded by people who care for her and about her! The more you think about the positive, the better the transition will be for everyone. Expect it to take a while for you, your husband and your daughter to get in this new groove -- ind of like it took you a while to get into a rhythm when your daughter was born. Also, remember that this is as transition for the daycare as well. It'll take a little bit for the providers to get to know your daughter & your family.
When my daughter was this age (and attending day care full time), I used to take her in a little early & nurse her before heading off to work. It gave her a way to settle in with the daycare while Mom was still around. It gave me a chance to get to know the care providers better and understand how things worked there. I just sat in a rocker in the corner with a lightweight receiving blanket over my shoulder & my daughter's head for about 20 minutes. Worked for us! And the lead teacher in the daycare was terrific & very open to the idea.
It WILL be OK -- really! A quality day care shouldn't make you said but excited for what it can do for your daughter -- and it can become a great resource for a mom as well.