I remember we learnt the basics/combined subjects in year 7 and 8 which was completely irrelevant! I just did my gcses this summer, and got 2 Bs in core and additional. In year 9, the courses got separated and even switched exam boards half way through the year. Some of the stuff was in there but was mainly just year 10 and 11 things, so I wouldn't worry because it is the start of the year. But it might be worthwhile starting a few revision notes so you don't forget anything by the time it comes to your exams like I did and had to relearn a lot of it! Good luck.
Remember to print off the spec too, as this helps you to know what you need.