What am I doing?

I'm sitting here instead of being constructive.  I'm leaving for Chicago in 36 hours, and I haven't even started our packing. 
I know exactly why I'm nervous about this trip.  Usually, I'm traveling in my car, and I have control over what I'm doing, or else I'm traveling with some other responsible person.
This time, it's just me.  I'm traveling with my daughter, on a bus to Chicago, with some other students from her school, for a field trip.  Essentially, it's just me and her.  Very few people she knows are going on this trip, and I'll only know some of the people in passing. 
(This is how you get scammed into agreeing to a trip like this.  Your lovely 11-year old daughter comes home in September soooo excited about this middle school field trip to Chicago.  And EVERYONE'S GOING!  And she can't possibly be the only one not to go.  And you will ruin her life if she's left out of this.
So you agree to go.  And you send lots and lots of money in, and bake hundreds of brownies for bake sales.  And then she mentions her two best friends aren't going.  And you say, "Oh, who is going, then?"  And she mentions maybe, oh, five people from her class are actually going.  Everyone else had dropped out long ago.  Because they knew better.)
It's really simple.  I'm terrified that I'm going to forget something essential and I won't have my car to go and buy it from Wal-Mart.  And I'm extremely nervous about the fact that I won't know anybody.  Who will talk to me?  (Interject my daughter: "I'll talk to you, Mommy!".)
I've been to Chicago twice before and it's a really wonderful place.  I'm sure once we get there I'll be feeling better about the situation.  Wouldn't it be cool if we could just skip over the apprehension we feel sometimes, and get right to the thing?