I was the same and made the exact opposite choice! I originally wanted to take English Lit, History, Art and French, but after GCSE I couldn't bare doing essay subjects at A-Level. I did achieve an A in all of those subjects, but I hated the style of the essay based exams and found revising them boring. I decided to take Maths, Physics, Chemistry and Computing which I achieved B, A, A and B for at GCSE.
The jump from GCSE to A-Level made me realise I had no clue at all when it came to revising. In GCSE I had relied on natural ability and light note reading, which obviously failed me in AS. I also suffered from some pretty severe mental health problems, felt alienated and stupid and hated the majority of my teachers and their teaching styles and ended AS with B, C, D, D, D (in Critical Thinking, Computing, Maths, Physics and Chemistry). I was at a point in my life where I began to doubt my self and thought that I was stupid and pathetic.
In A2 I completely overhauled my subjects, my teachers and got help. I dropped Critical Thinking and Physics (I was stuck between dropping Chemistry and Physics, but kept Chemistry in the end as I was only 1 UMS point away from a C) and changed teachers in my other subjects. I also left half way through the year and did some part time work and focused on myself and what I wanted for a while. I took a step back and realised that I could actually do my subjects! I came back to college in September 2015 and went from a D student to a A/B student and achieved A, B, B in my January mocks! I was in shock! My university offer is A, B, B and I'm reasonably confident of achieving this. My only worry is Chemistry, which I'm getting B's and C's in, but which I've realised just isn't my thing.
Sometimes I wish I'd gone with my brain and picked at least some essay subjects, as I think I would have enjoyed History or English Lit and done well in them. Then again, if I'd have listened to myself and not taken Maths (due to my B at GCSE), I wouldn't be on track to achieve an A/B and I would have found it really hard to find a Computer Science degree that I enjoy (if they don't involve Maths they involve business related/web design style modules, which I don't want).
So to any year 11's, I'd say give yourself a balance. If you're torn between subjects, maybe try to have at least one subject that you're picking because you love, regardless of how 'good' you think you are at it and perhaps have at least one subject that you think you're really good at. At the end of the day, regardless of what you pick, you'll probably have some 'what if's. If you already have a degree in mind, see if there are any prerequisite requirements! That's the main reason I chose Maths even though I had 0 confidence in it. If you pick a subject you end up hating, you can always switch if it's early on in the year, or drop it, if that option is still a thing when AS exams are gone.
And one last thing. At GCSE, if I had trouble with something (for example, a whole topic, not just one question), I just read online or asked friends. At A-Level this did not work for me at all and I had to work up the courage to ask my teachers for help, because asking for help and admitting I couldn't do everything made me feel really stupid. Don't feel stupid if you don't get things right away and don't be afraid to ask any teacher for help, even if you don't have them for lessons (if, for example, your teacher is off sick or something)!