Postgraduate fees are high? Where did you get that? It's all HECS these days, so essentially it's "free" - technically not free - but no out of pocket expenses.
Well a doctor and a pharmacist are two completely different fields of work, surely you would have come across doctors and pharmacists before, you probably know a bit about what they do and the environments in which they work.
Btw, what's this about fees - don't worry about fees - you don't pay anything, it's all HECS
But if I cant pay the fee and have high ATAR, I cant get into the course I want. Becoming a doctor is very hard. Thus I just consider about pharmacy as well, just in bad situtation 
Well becoming a doctor is hard, I'll give you that, but if you want to become a doctor, you have to take that challenge.
But becoming a pharmacist isn't easy either, it's very hard to find good employment these days, according to friends who are doing pharmacy.