Hi, bananna!
With regards to the post-trial period, it's definitely normal to feel like not doing anything. Final major exam is done, all you want to do is sleep on your troubles (no? just me? ok lol). I recommend relaxing until you get your trial exams back. Doing studying and buckling down before receiving feedback is useless, because studying habits are derived from what was working and what needs to be changed. So, take the time to congratulate yourself on getting past the trial stage. At least until you get your results back.
When you do get it back, don't hesitate to ask your teachers for further confirmation to see the areas you need to change coming into the HSC. If you've received wonderful trial results, then that's great -- keep going. However, don't fret if you haven't. You still have plenty of time to get yourself back on track before the HSC. So, consult and use your teachers as much as possible. Ask questions. Become proactive with your results.
If you haven't already, now is the time to create a schedule for your plans throughout the week and stick with it. Prioritise time to yourself; spend more time to cater to your weaknesses, but don't neglect your stronger subjects.