Should I retake year 12?

I’m currently in year 12, studying maths, philosophy and psychology and I am considering repeating year 12 for a number of reasons. Firstly, I am actually not supposed be in year 12 but in year 11. I recently moved to The UK from France and made a mistake whilst applying for schools and only realised it when I had to take my baseline maths test 😭 but my school gave me a chance to retake and I got a good percentage. I absolutely wanted to do further maths but couldn’t because of this. Moreover, my school is only offering AQA PRE (philosophy, religious study and ethics) so the majority of syllabus is around religion. Whilst religion is interesting, it is not really my centre of interest in philosophy. If I repeat a year, I could do pure philosophy which I believe I would enjoy way more. But, I don really have a problem with my grade (A,A,B). So, would it be a good idea to repeat the year?