A level predicted grades

Hello, I've done my Maths A-level exam today and I feel a bit unsure about it my, my feelings are that the grade I got would be about B. Now my predicted grades at the end of two years is an A. My minimum target grade is a C and my current working at lvl is B. If I get a B or a C would the school be likely to change my predicted level? And what would most likely cause them to change my predicted level from an A to an A*? The level of work I am putting in class and grades in weekly exam or just grades based purely of the exam I have done today and the next mock exam (summer or beginning of next year not sure). The next question I would like to ask if it's true that universities look only at your predicted grades as by the time you apply you won't have your results yet?
Edit:
I know these questions might be hard to answer as it might be dependent on the college, however I would like you guys to share some info with me if you have any ideas or tell me from your experience, any comments are appreciated!