I'm sorry. :( I know the encouraging thing would be to tell you it will be fine (which it will, for her) and it will get better, but I was a wreck when DS went into daycare.
I cried for like the first week he was in daycare. I eventually dropped to only two days per week and now when I go back to work it will be only PRN or as needed. To be totally honest, it never got better for me, I always missed him so much and had a really tough time, which told my husband and I that we needed to get our finances in order so I could work less.
I hope the day goes okay for you and it does start to get better for you.