I felt bad after I posted yesterday. I like to think that it's not really "me" to get upset about little things like that. (Except when it is, eh?) Honestly? I'm sure the field trip will work out fine: everyone will have a good time, and in retrospect it will all have been worth it. I guess that sometimes it's hard to find that balance between planning for the future, living in the moment, and reflecting on the past. What can you do, though?
Just keep practicing.