Kini - she does tend to be rather persistent with her persecution doesn't she
Rightly or wrongly I've acclimatised myself to take it as her way of demonstrating "affection", for the sake of your own self esteem, i reccommend you do the same!
Ashwin - NIDA is part of UNSW, but it has a separate application process. They don't tend to take school leavers as they find they lack "committment" (or so my theatrical friends have told me), and they usually prefer to take you after you've done either another degree or some other form of course etc (get the restlessness out etc...) I don't think there is a capacity to do economics in conjunction with a NIDA course, but maybe it's best you do the eco degree and then apply to NIDA afterwards. Also look out for summer courses and get involved in uni revues etc so that you can present them with a resume of experience...they may also come and view you in those performances!
Ring NIDA and find out!