Are you at the beginning of your second year?
If so I would suggest quit worrying about grad school and instead focus that energy on improving your study skills. In high school it was so incredibly easy that when I came to college I realized my study skills were grossly underdeveloped and I didn't do so hot those first few semesters. However the further I've gotten into my undergrad career (I'm a senior now) the easier and easier studying has gotten and the higher and higher my grades have gotten. I've brought my gpa up from a 2.8 to a 3.4 so far. Perhaps you should just really figure out what really works for you in terms of studying. And just f.y.i, I noticed you said that you memorize things, which, IMO, is a big no-no in terms of good study habits.