I feel your anxiety!! I'm not a nurse yet, but I'm starting a second career after 20 years in my previous field. So, what I can tell you is more based on my experience as an EMPLOYEE than anything else.
1. It's the people. Talk to adults with 10, 15, 20 years work experience, and they will all tell you that the people you work with will make or break your job. ALWAYS people will say "I'll miss the people, not the job" and that's just kinda the reality of it. As people come and go, jobs that are good today might be crappy tomorrow- a new supervisor, a merger, a restructure, a few people retire/transfer/quit, etc and you have a totally different situation. Sometimes better, sometimes not. So, my first thought when I read your post- was to ask how the people are that you work with. Are you a team? Do they "have your back" do you all work well together? It matters, BIG TIME. Like others suggested, maybe a scenery change is all you need.
2. You can chase degrees all day long- heaven knows I did that trying to find the best fit for the second half of my life, but at the end of the day, nothing is perfect. School is school, work is work. Retraining, re-educating is time consuming and expensive. If it were me, I'd exhaust all possible avenues with existing credentials before moving on.
My mom worked as a RN for 45 years before she passed away. The majority of her early years in peds, then the bulk of her life in ICU/CCU. When she became a "senior" and wanted less stress, so she earned a degree in culinary arts lol. After 4 years as a cook, she hated it and went back to nursing. My point is, your quality of life is important- it's worth trying new things, sometimes they work- sometimes not. But, there are always options.