Generally speaking, an ME CPL IR with sufficient hours will mean a lot more to an airline than your A levels, GCSEs or even a degree.
In the UK, I have never seen a uni degree as a requirement for any piloting job (though I haven't looked at every single job out there, mind you) and the most I've seen is you must be qualified enough to be able to get into university. Your geography and physics A levels should put you in good stead.
I saw a sponsorship scheme recently, I think it was for flybe, that required an A-C in Maths and Physics at A level. I can imagine they get a lot of applications for a small number of positions, so would be surprised if anyone without these even got to an interview stage. That said, they are paying £20-£30K for you, so for other jobs it shouldn't matter.
And for the record, I did maths and physics at A level, and am currently doing my ATPL grounschool, and so far am finding that my physics knowledge is hundreds of times more useful than anything I learned in A level maths. So on that level, do not worry! I also did geography A level, which is proving pretty useless, but I did get awfully good at colouring in