L.A.
Ah Bless your heart. It is very normal.
First.. Remember to take a photo of your child that morning. Pick a spot on the front steps or next to a tree, so that every year the first day your child can be posed there..
My husband I had to suck it up also.. We did not want to upset our daughter. Lots of big breaths..
We just matter of factly walked her up and asked for a hug and kiss, then we told her "wow, look at all of your new friends!" "Go and have fun! I will be back later to pick you up."
Then we watched her walk to the table and sit sown next to another little girl.
You could maybe look around for another set of parents with a calm looking child and say, "look at that little boy (or girl) she is going to be one of your new friends. Do you want to follow him?" Or "do you think we should follow him?"
The secret is to get them in, tell them good bye and then turn and leave.. Do not look back. Remember the teachers are trained on how to handle the different emotions of the children.
You just need to get to the car. Take tissues and maybe go with your husband or a friend for breakfast.. Talk it out.