I think all babies are different! If she wants the amount you are giving her, and is otherwise a happy baby, I think your doing fine! She could be having a growth spurt, and you'll find in a few weeks she might not want as much. My son drank a lot more at this age than my daughter does now, and they are both considered healthy!
My daughter definately tells me when she is full. Will be drinking away and then all of a sudden will push the bottle out with her tingue, and there is no way you can get it back in!