Schweser Practice Exams Feedbacks

When you’re doing practice exams, do you ever feel like you don’t know the answer for sure, but make “educated guesses” a lot? I’ve been experiencing that while doing the Schweser Mocks. It makes me feel scared when I do them, but I’ve been getting just above 80% for the practices… Is what I’m experiencing normal? Or should I really go back to the CFAI books (which I hardly read) and solidify my understandings, so that I don’t have many of these “educated guess” moments?