School Anxiety

I have been so excited for H1 to begin school and to experience her next step in life.  She turned 5 in Mar and begins school just after Labor Day weekend.  We were able to check out part of a class in the spring and she was amazing.  She was quiet, attentive, excited, and oh so eager to experience everything.
Her class is going to have 22 students in it.  At first they asked all the parents if we wanted them to split up such a large class.  This is just a gentle reminder that we live in a very small town/tri-town area that consists of 400-800 people total (NOT EACH).  Since I grew up in Phoenix/Tempe, Az I was almost laughing at the question.  So many teachers there would almost kill to get a class that small.
Anyhow, H1 and I have been working on letters and writing (albeit not as much as I should have) and on her numbers.  She is doing really well in my opinion and amazes me frequently.  However, the other night I was laying in bed worrying that I have not done enough.
Have I read enough books with her?  Have we practiced her letters and numbers enough?  Does she need to know all those nursery rhymes, which by the way I don't know all of them, before school starts?  And then I started worrying about how the other kids are going to respond to her.  IS she going to have friends?  Will she be picked on?  Is she going to cry when she is at school or on the way?  THEN I began worrying about the bus ride.  Should I just drop her off at school in the mornings?  Will she be picked on if she rides the bus?  AAAAAAAHHHHHHHHH!!!!
Needless to say, I am having some issues.  I just want time to stand still so I can control everything.  I know my little girl is strong and amazing in so many ways and she is innocent.  Am I ready for her to grow up and deal with all the awesomeness that comes with other peoples children?
I am doing what I can to control the issues and continue to believe that this will be great for all of us.  It will be time for just me and H2, time with Izz Biz, time for me, and such amazing experiences and growth for H1.  I just need to get through the first week or so and then hopefully I will be better.