Yes, don't worry about it. In Y12 I messed up pretty bad for English Advanced and was getting basically similar marks (around 75%-80%) until trials where I got 90+ and ended up getting a 94 for HSC english. Don't worry, it might feel like a lot already gone so far but don't forget the HSC is worth 50% of your total mark! If you put your head down you can definitely still do well and get a 90 ATAR 
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