Alright, it's important to remember you still have at least 60% of assessments left to boost up your rank. I'm not going to stress the importance of doing well internally, because I think you know that, but you really have quite a big chance to boost your ranks with that >60% weighting of assessments left. Understandably you are upset over your ranks; it's normal for us to feel emotional and panic about our results and not think rationally about it. But I would strongly advise you to stop worrying, simply because it when we overthink, it does not benefit our well-being both in the short and long term.
Instead of acting emotionally, think strategically and ask yourself: "How can I be smarter in my preparation for future assessments?" See these ranks as a merely another hurdle to improve your academic ability as you seem capable of doing well, from what I've observed on the forums.
Now, for your ATAR estimate, but keep in mind, a HSC course is very different to their prelim counterpart in every subject. Anyway, for your estimate, I'd say you're looking around 90, but to be honest, I'm a layman at ATAR estimates, so try to get some more.
You seriously need to work on your Physics. It's going to count no matter what (since you're doing 11 units if you take into account accelerated business studies). And even if you do well in subjects such as Economics and English (relatively speaking), Physics will drag down your ATAR considerably. So, I suggest getting a private tutor, perfecting your exam technique as simply rote learning the content is not enough, and going to seminars, etc.
Not to mention it wouldn't be enough to just improve in the other subjects. Improve all around and your ATAR will improve all around. Additionally, focus some of your time on improving maths, especially 2u, so a) you get better marks and b) then you could also do well in 3u, where scaling helps.
Just consider all this and good luck!