I think hvert's advice is good. Do go to a few seminars for nurses (anyone can attend if they pay/might find a freebie) to see what it feels like to be around others in the field. Take a class to see if the interest continues (I suggest a hard-core one like Anatomy&Physiology--with your social anxiety, this might be more appealing than the classes where there may be role playing etc.---you can work up to that) Know that nursing school is not easy, I don't mean academically so much as emotionally, you have to keep your long term goal in sight. And know where you want to go (eg: to continue on to a Master's level so that you can be a clinician/researcher/teacher...)----
I did nursing school many years ago in a state of extreme depression and anxiety----& I did well ---I had already been working in health care which I am sure helped me----I also ended up with a good group of students & we supported each other throughout.
GOOD LUCK! (One of the more difficult things I recall is learning to ask people personal/intimate questions to gain a good history/working base----it got much easier over time)