Will not choosing maths matter?

If you're trying to get into computing maths if definitely a big bonus but its not a killer if you don't do it as the average university often starts out with GCSE-level maths, so as long as you get good grades in the subjects you have chosen you'll be fine

Only top Unis ask for maths

Thanks a lot pal, great to hear that as i feel i may be too late to even change my options that's helped to ease my worries. Appreciate it.

As I remember it, you can still change your A-Level choices for about a month or so into the year, so its definitely not too late to pick it up, and if you didn't get the required grade, just know that's all set by the school, not some legal thing, so if you ask them nice enough and act passionate enough about it they will probably let you take it