Lost at School

My daughter has been in kindergarten for several weeks now. We are starting to get into a routine with the homework, making lunch and the drive to and from school. She seems to really like all of her classmates and teachers. I on the other hand become more and more shocked on how long it takes to complete kindergarten homework. I was even starting to get used to her attending such a big school until this passed Wednesday.
 I pray everyday that my daughter is safe and sound at school. I have tried not to be one of these over protective parents. But I still don't feel comfortable in dropping off my kindergartener in front of the school and watching her walk into school yet. I have tried to break the reigns a bit. I do let her walk in front of me and I watch how she encounters all the bigger students. (If you have not kept up with this adventure of ours, my child attends a school where Elementary, Middle and High school students are all together). Some mornings she will stop and look around, then other mornings she heads straight to her locker and hangs out with her friends outside of her class. As mommy stands alone watching from the side with all the other parent, who are not ready to leave their child's side.
This past Wednesday was like any other school day I thought. We made it to school on time, I gave my little one a big hug and kiss and watched her walk into her classroom. I thought she was safe. I have noticed I have started this routine where I always call my husband when I know school is over to make sure he had gotten our child picked up and to talk to my little angel. My husband never answered his phone that day. I finally was able to talk to my little angel that afternoon and the first words out of her mouth was: Mommy I got lost from my class today. I was using the restroom and when I came out of the restroom, my class was no where to be found. She went on to say that she walked to her classroom and the lights were turned off, so she walked back to the foyer where her gym teacher was sitting and the gym teacher took her to the office. Where the office had to call for the aid to come get my child.
 As a mother sitting at her desk at work what would you have done at this point? I wanted to run to my little one and grab her and give her hugs. I was also in shock. How can you lose one of your students? Why was there not a head count preformed before leaving? I wanted to get to the bottom of this. I guess it might have been the best thing that I was at work and not picking her up. I could tell my husband was not happy. Could you imagine how a pregnant lady would have been. My husband said he talked with the teacher and the teacher knew nothing about this, and that he needed to talk to her aide, whom was gone for the day. I am sorry, I thought the teacher was responsible for her aides actions and her students? The next morning, I got the chance to talk with the aide. She said she was very sorry, after the many umm umm umm's, when I asked her how a child could get lost from her class. When I asked why there was not a head count done, she said we will need to start doing that. HELLO, that should have been in place the first day of school!!! As I was talking with her she seem to try to place the blame on my child some what. She tried to tell me that my child was not alone for that long of time. The gym teacher was right there. Also she had a talk with my child about the accident. As a pregnant mother, who is the last stage of pregnancy this did not set well with me, but to keep my self from going into labor, I bit my tongue.
 I now have 2 somewhat different stories. All I know is that my child was by herself lost in this really big school. Thank GOD she knows better than to walk out the front doors without an adult being with her. It was not my child's fault she got separated from her class. She is five years old. What do we do from here? Should I wait to see if it happens again or should I demand more answers? I am still debating on having a conversation with the principle about it. Tonight is open house. I am hoping to shed some more light on this subject. I would like to talk with the gym teacher that took her to the office.  Or should I let this play out?  Many of my friends have told me different things. I really don't want to make enemies this early on in the game. My child will be at this school for many more years to come. My daughter has a field day and many fields trips planned for this year and I am more terrified that they are going to leave her somewhere. I just don't know what to do.