I did a career change, and I've actually never really felt as if I was in a subordinate position to a Physician. Essentially we have different roles and do different things. (I've got a MPH and a BA, as well as a BSN)...I don't feel underemployed with my paycheck.
I've found many times, the physician comes to me and asks me directly what I think is going on with my patient...we have a conversation. I suggest some things, the doc suggests some things and a plan of care is made. It isn't that way in lots of places, but everywhere I have been, its been this way.
The only trouble I have had, right now I am traveling, and I am going to some really rural hospitals. I find that I don't relate very well to some of the nurses who are great nurses, but very "local" people. They have told me "you read too many big books, use too many big words, and go to too many exotic locations (florida...)"
As I always suggest with career changers, try to do some volunteer work in a hospital or something related to healthcare before jumping in. I've met so many unhappy students who had an image of nursing that just didn't match with the reality....