Asking for Constructive Criticism after interview

It wouldn't hurt to ask; it would show that you value her feedback and want to better yourself. Worst case scenario, the nurse manager is too busy and doesn't have time to respond. I don't think it would be out of line. Something like "I enjoyed our conversation and learning about ____. I am disappointed that I didn't get the job but I understand you must carefully choose from many applicants. If you have time, I would greatly appreciate any feedback that could help me with future interviews as I am still interested in employment with Hospital"

I'm from the old old school in which the application and interview process was more civilized and professional, and applicants weren't treated with disdain, as though they were a nuisance to emplyers. In today's world I think it would be offputtin to contact an employer after you were denied employment, for any reason. There's a post in here describing how online aplications are even rejected before they are completed, much less submitted- that is very telling. In this strange new world of oversupply of nurses, I think you're best bet is to send a thank you card to the interviewer, for her time, (to leave a postive impression, rather than possibly annoy her by contacting here for an explanation) and leave it at that. Maybe you can desrcibe your interview to a collegaue, or a job center mentor, and ask if they feel anything you describe about your interview may need tweeked for your next interview? Even so, you're never really going to find out why you weren't offered a job, sad to say.