@RhiJaneJoyce,
OK, that makes sense.
The good news is that you won't be bullied in University. Especially in a good University there is none of that nonsense. The people around you will be as smart as you are, and everyone is there for a purpose. You should definitely feel optimistic. Things get much better once you get to University.
I agree completely with you, a diploma in Enrolled Nursing is not a good way to get to a fascinating career in science.
If you have the curiosity, brains and the desire to be a scientist, then by all means you should make that happen.
It is difficult for me to give you specific advice since I don't know very much at all about how education works in Australia. But if it were me, I would go and talk to colleges. There are admissions counselors in colleges who will speak with you. They will tell you exactly what you need to do to be accepted into their programs. You might be able to talk with a guidance counselor at your secondary school who would help. For that matter, talk to anyone who might be able to help you.
In the US, your grades are important, particularly in 11th and 12th years to get into a good science program. You have a couple of years to work on this (I don't know if this is an issue).
My best advice is to go for it. If you want to be a scientist, then make it happen.