For first year B.Science, I had somewhere between 19-22 contact hours per week depending on when I had pracs. If you compare your timetable to someone studying Commerce or Arts, you'll realise that Science (and maybe Biomed???) have the most numerous number of contact hours. Unfortunately, as you continue through uni, Science kids will probably have more contact hours than the other bachelors. I'm in second sem of my third year and I still have about 16-18 weekly contact hours.
But on the upside, the more hours you spend in class, the more friends you can make in your subjects and you'll soon realise that friends are one of the most important things for later years when you're struggling with a concept or topic !