The problem is, apart from 3 unit calculus, and 4 unit maths. The rest of the HSC maths course is essentially a foundation for higher mathematical learning, for example permutations and combinations are used in error detection systems in computers.
In medicine they mostly part an important part in research, for example the spread of disease through an particular area or community. In more micro scale, calculus can be used to calculate: the approximate growth rate of an tumor, and the rate of flow of toxins through the body, and much more.
An example of using parametric's is in bridge cabling, as they hang down in an parabolic function. Like here:
As a matter of a fact this curve can be given by this differential equation:
Where
is Kilos per metre and H is the horizontal tension of the cable at the origin. (where is origin is at the middle of the cable.
And I haven't even mentioned actuaries *shivers*
Also if you get into an job such as engineering, you'll have to make up your own maths questions, and solve them amongst a team of people, so you can be confident that most mistakes will be picked up. So if you are going into this field it is a good idea to start becoming mathematically curious, try to get yourself to think outside box and create your own maths questions, and solving them without help from other people.
Anyways you'll probably realise how incredibly useful maths once you completed physical applications of math.