Nope, not for a minute. I wanted to quit nursing once, but that was because I absolutely hated the clinical rotation I was on (geri) and thought that meant I hated nursing altogether. It turns out I just hated that rotation, and I absolutely love ICU and paeds.
However, I am strongly considering doing medicine at the moment. I do doubt my intelligence - and my ability to get in - for that.
Also, how cute is this?
ETA: The RN program in Australia seems to be far less intensive than yours. It's a three year degree, and I'm not saying that either produces better nurses, or is harder than the other, just that we don't seem to have the stress that you guys do.