lol, I have the same feeling, I sometimes think what if all my hard work doesn't pay off or I don't get in> then i think to my self, its only one month till Umat and just study hard, you will get in hopefully, if you have done all the hard work.
Taking a gap year would be great, as it will allow you to focus more on your career pathway and also maximise you chance of preparing well for the Umat. Umat is very stressful at times, even when I start to prepare my head goes blank at sometimes.
I would do the same thing as you if I don't get in the first chance, I think you can do medical and advanced science degree, then in your second year can plan to transfer to medicine, lol
I have a question, can you do advnaced science in UNSW and then transfer, I am not really sure about this,
Here is my Emial: you can let me; if you want to join my Umat prepare group, Its only me an one of my friend, which prepare together every Saturday from 9.30-4pm in Blacktown Liberray.
Your welcome to come and join us, and we can all experience doing questions and sharing our tips.
Good luck, bro