just like any job, the longer ur there, the more chances you have at making more money.
my Aunt has been a nurse for 25 years this June. and she makes well over 100k+ a year (she does 3 12 hr shifts a week, and some per dium mostly every other day. she isnt burnt out at all, because she has the 12 hr shifts under control and is very used to them. as far as per dium she takes it as it comes, and does refuse to show up sometimes, and with the perk of having seniority at her hospital that is A-OK!
also, i am in my first year of nursing school , SO HARD, and im not doing it for the money, tho the hospital that my schools interns go to, does Hire anyone at my college, mostly all that apply, and start them at around 60k a year.
so... i guess it depends where you live etc. But, i agree, DONT do it for them money, because if thats what ur in it for, your up for a VERY RUDE awakening. if you do your job good and enjoy it, then it isnt really work