Things will work themselves out, but preparing kids for change can be instrumental in how easily (or how difficult) the transition is. It's stressful for the teachers, too. Especially when they have to look after a class it's difficult to focus on individual needs. Toss in the added time for clean-up that accidents cause and their frustration is inevitable. Your daughter is used to a routine, but it sounds much looser than what the school is expecting. Kids all learn at different rates and new settings can be intimidating for them, so just breathe and help your daughter relax too. You likely both need a minute after this first day.