The more you want it, the more it'll show. I got ABC (C in English) in AS after a year of not really caring what I was going to do with my future. Then in the early stages of A2 I realised what I wanted to accomplish, I put my arse into gear, got my head down and improved my grades to ABB (a high B in english!). May not seem like much, but it was obviously enough to satisfy my firm choice so I'd say you have a very good chance. You seem very eager to do well, and that will drive you further than you may first have thought.