It's definitely not too late. I'd take a step back to look at your current lifestyle and how much work you're putting in to school, it's worth it. Even now, when my marks have improved a lot for year 12, I access myself and ask myself how I can improve.
Trust me when I say that it's not good to cut out your relaxation and fun times; they're just as important to your performance as studying/working on folios. Create a timetable and put in the stuff in your life that you don't want to miss (ie, your job, sport practise, etc). Then plan your study around those times.
You've said that it's getting harder. I've found that too, and it helps to distance yourself from all the people who are freaking out before SACs. Often, they're a distraction. I know it's nice to know that you're not alone in feeling worried, but ultimately, it just makes you worry more instead of doing something to make yourself feel more prepared (I learned my lesson from psychology last year).
So ultimately; yes, you still have a chance. Exams aren't for a while and we're only midway through the year. Do your best from now and you'll see the results
