It does not mean something is wrong with you just that some classes/subjects do not come as easy as others, which this may be one for you so if there is additional help available please take advantage of it. Use a help desk, find another student to study with, or find a tutor. It is amazing the difference it can make in these situations. We all can use a little additional help some times; we just do what we need to to get through and to understand the material, even AP and honors students. Hang in there.