Well, I'm a nurse who has always intended to do midwifery (when I finished my general training at 20, I felt I needed a few more years of "life experience" and work experience before doing my mid - a decision I do not regret). I have worked in general medical, aged care and now I'm in NICU. I understand your feelings about the study - I found the course to be long winded and in all honesty it didn't really prepare me for the "real world" both in terms of clinical experience and knowledge and in realistic expectations of what nursing was like.
I think that compassion fatigue you are describing disappears very quickly - most first year nursing students have this idea of being a little Florence Nightingale and just want to "help" everybody and hold the hands of the dying etc. Not saying this isn't a part of nursing, but it takes on a different shape to what you initially picture yourself doing. I think the hardest things about being a nurse is the shift work, the frustration of not being able to do your job as well as you want to simply because of time pressures and work overload and patients that no matter what you do, will either not like you or will not take control of their health and want to blame you... That said, since I have started in special care and NICU I have been much happier and more satisfied with my job and find it very rewarding. Like teaching though, parents can be a difficult part of the job... and you have to have a thick skin. Most however are lovely and very appreciative of the care you are giving their baby. Unfortunately it is not a job that you are likely to get immediately after graduation and you will no doubt have to do your time in positions that you don't love and you have to do them well so you get good references.
I've never really considered teaching but I imagine it has many of the same frustrations of nursing and that reality of the job would be different to expectations of the job.
If you have any specific questions about nursing or NICU you're welcome to message me
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