Its not just you. My school has no clue what's going on either. No one knows the grade boundaries so its very difficult to place everything. But using the new system is what's best for now so everything will be clearer in the future.
You should really count yourself lucky, at least you won't have to do coursework in English. That was a pain in the butt.
the only subject i have coursework for is health & social care which is entirely coursework, other than that if i mess up my exams i'm pretty screwed lmao
1st quarter I had straight A's but now 2nd quarter I got all A's and one C -_- dang algebra But usually I always have straight A's like last year.