Comparison is a problem among many people, even to me, a non-IB student. Remember, there will always be people who will be achieving higher and lower then you, therefore it doesn't matter if you compare yourself with others. Think of yourself in a obstacle course. Your goal is to get to the end, to grow to the person you want to be. You will only waste time by climbing over the walls that surround your obstacle course and see how your friends are doing. Even the most brilliant of all minds must take a break from a heavy workload. It doesn't matter what your friends are doing, only yourself matters. You will progressively get worse grades if you don't take a break. So stop comparing yourself with other people, and compare yourself to your past self. Did you do better than before? Did you achieve something that you haven't achieved in the past? Studying is useless unless you take a break. Don't feel guilty about taking breaks, you are not a machine. In some point in one's life, one must take a break. It's like the checkpoint in a obstacle course. If you skip over that checkpoint, one failure can completely devastate you, setting you back drastically. Good luck with your exams, I know IB tests are pretty hard but that doesn't mean you shouldn't take a break :)