I got off of work early today, why do I feel so guilty?

I’m a high school teacher and usually work 7-5 with a 45 minute lunch. I left at 2:30 today because there was zero reason for me to stay, but I feel like I owe someone an explanation for leaving early and I just don’t think I do. Weird.<br><br><br>Edit: I do not get paid hourly, I’m paid a salary. I’m also the only teacher in my department so I do have to stay during the school day most of the time.