I think that each course has it's own set of difficulties. A&P was very tough and involved studying EVERY day. My nursing courses are tough and still required studying every day, but the difference is (while both involve memorization) nursing involves ALLOT of critical thinking. You always have to think ahead, expect the unexpected, and realize that, like A&P, each course builds on the other.
A&P is used throughout nursing, even in the field, making the stress of learning it more abundent. It is your first BUILDING BLOCK, in nursing. It is also one of the most important knowledge based courses in the grand scheme of things. A&P is also what makes or breaks allot of new nursing students. They don't realize how difficult it really is and many aren't willing to give up the "fun part" of their lives in lieu of studying.
I still highly recommend that you take at least one day (at least part of a day) where you don't even look at a book. It helped me get a B in A&P. Don't be afraid to ask questions or ask for help. Don't be afraid to TELL friends and family that you can't participate in something because you have to study.
I know I'm rambling, but it is very important to understand that ALL classes have their own set of difficulties, but A&P is one of the most difficult because of the memorization and having to remember EVERY detail for every nursing class in you nursing curriculum and in the field.