I have a state exam to study for and I can't drag myself to open the book. I keep getting so lazy…

I have a state exam to study for and I can't drag myself to open the book. I keep getting so lazy and tired how can I counteract that I have 13 days till testing and my pregnancy brain is really bad lol every time I take my books out I don't end up opening the page. It's like I want to but I don't want to