I’m in year 12 currently studying Maths Economics Physics and Chemistry. Physics was so easy at gcse but in sixth form it’s so different. But as long as you manage your time and revision it should be calm. It’s the hardest subject I study. Chemistry is actually calm. I would get B’s and I got an A. So you definitely can get an A for chemistry. As for Maths now I’m good at it cus I’ve actually done the most revision for this but some people don’t like it and find it very hard. Chemistry you should pick, it’s fun never boring. Maths if you’re good at it. If you struggle with topics in gcse physics then you should really reconsider picking it. I’m pretty sure you can change your subjects on results day and the first week of Sixth form. Don’t stress it. Career wise physics is most rewarding subject, it’s a highly respected A-level. Any type of engineering physics is pretty much required or highly preferred. Chemistry also opens a lot of doors for courses to study at uni. Most unis actually prefer students with 2 science subjects and one of the maths.