Amount of A-Levels to study

I was going to do the IB instead of A-levels, but now I know i've decided A-levels are probably best for me. I wanted to do 6 A-levels in Maths, Further Maths, Biology, Chemistry, Physics and economics, but I'm not sure if i would be allowed to do this. Right now i am studying 3 languages, french being the languages I've been studying since year 7, and German, and Spanish which i've started in Year 10 with no previous experience. I was wondering if 6 A-levels would be too much, even if i am able to study 3 languages now at GCSE level. also in uni i am at a crossroad between studying economics and medicine