It sounds like you're doing some great thinking about future directions and about what's really important to you. I hope that your career decisions will be based on a lot more than what you read here. A safe place to vent is nice for anyone to have. We're lucky to be able to come here and share experiences. The intent is usually for us to be heard by people who understand the frustrations, but it's not meant to scare off people who are looking at nursing as a career.
To me, entry level education is a big difference between psychology and nursing. With an undergrad degree in nursing, you will ultimately get a job being a nurse. It can be much different than you imagined, but you'll be a nurse in some capacity. With an undergrad psych degree, most people end up either working outside of psychology or working in a completely different role than they imagined.
The schedule as a nurse can be tough, but keep in mind that it comes with some opportunities for flexibility. If you want to work only weekends, or to be off every Wednesday, or to work some other random schedule, you can probably find an opportunity that will fit with that. And when we work the stuff that may be less desirable, like nights or holidays, that usually means more money in nursing. With jobs in schools, you'll get less of the crazy schedules, but your hours tend to be less negotiable.
There is a great deal of stress in nursing, but I wouldn't assume that school psychology is going to be a walk in the park. My mom (an elementary schoolteacher) was chased around her classroom by a student with a pair of scissors a few years ago. Granted, that's not a typical day, but kids are getting crazier instead of calmer and you would be working with those high-risk populations. Stress should be a concern for someone who worked in a school just as much as it would be for a hospital employee.
It sounds like you're off to a good start. I don't mean to steer you one direction or the other, but just to give you some other things to think about.