Fonzerella, I childminded my friend's dd when she went back to work when her dd was 11mo. We met when we were pg and saw each other at least twice or 3 times a week after our babies were born at various activities or at each others houses so her dd knew me well and was familiar with my house and my ds.
The first settling in visit, she cried for the entire hour. The second visit she still cried for the entire hour. I did absolutely EVERYTHING I could think of to comfort her but she just cried and cried.
The third time I had her was my friend's first day back at work and her dd was due to be with me for 4 hours. She cried for the entire time she was with me, despite me carrying her round, cuddling her, trying to distract her, etc. She stopped for a while when we went for a walk but started again as soon as we got back to my house and she realised her mum wasn't there.
It was incredibly difficult for all of us and I know my friend contemplated stopping work altogether. However, her dd did settle with me once she got used to it, she still cried everytime her mum left but she calmed down straight away.
The point of this rambling is that all children are different and some are just more sensitive and react more strongly to changes in their lives. I don't think the nursery can be blamed for being unable to calm her down, or that you should worry about the quality of the care there. Your dd sounds as though she is just missing you and uncertain about her new surroundings so she is letting them know in no uncertain terms!
I'm sure on Monday she will cry, but she will calm down too, and the more she goes and becomes familiar with it, the more settled she will become.