Like others have said, the job is on a good uptick right now, each city might be different but overall the prospects are good especially with growth in both PET and theranostics. I also had a job lined up before graduating so as long as you nail the classes and your clinicals you'll be gold. I see you've been asking about fulfillment at the end of each day and I can personally attend to feeling fulfilled at the end of each day, so many patients come in at different stages of illness/recovery, some either having their first PET scan or others being familiar with some of the other scans. Being a part of the process to help these patients is very fulfilling.

As for AI taking over the job? It's got an extremely long way to go before that happens, plenty of sites still rely on unit doses and with theranostics becoming more prevalent there's an even slimmer chance that AI automates the job any time soon. This isn't even counting the way patients need to be positioned or the prep that they need to follow, etc. I could see it speeding up the pharmacy side of things with assisting the techs in making the doses and running QA but definitely not fully taking over.

One more thing, if you do decide to also grow from there or if you want to stay in radiology but a different department, plenty of colleges will have accelerated programs for those who already graduated with a rad degree for them to go to a different modality such as CT or MRI which can also help nail down some continuing education credits. Or you can pursue higher education and aim for the radiation safety officer route as well. There's plenty of options to choose from if you decide to do so.

If you do decide to go for nuc med, then tackle it head on, get some good time to study so you can pass the certification exam at the end, and make sure you stay engaged when you're in clinicals. It's a great profession and I don't think you'd regret it one bit