The ENTER required for your course has more to do with demand than with course difficulty. You wouldn't be wasting your intelligence on a course with a lower ENTER score, because all that means is that you're picking a course that isn't all that popular.
If nursing is truly what you want to do, then you have to go for it! You shouldn't just pick something else that requires a higher ENTER and will ultimately leave you unhappy. However, if you decided that you wanted to do nursing in the first place because that's all you thought you could get into, you really should rethink. Somehow though, I don't think that's the case here.
All you need to do is ask yourself if nursing is what you want to do with your life. If the answer is 'yes', then everything else is irrelevant.