I think that those A Level subjects are really amazing, I am currently in my first year of A Levels doing the same subjects. Pharmacy is very competitive and lots of people across the UK apply for it so to make your application, you should consider doing Maths or Physics A Levels. If u do 4 A Levels, you would be able to quit one if you don't want to do it anymore. You also need strong GCSE's, at least 8 at 9-4.