After selective

Hi guys.
After selective exams, I was totally burned out so I kind of slacked off. Selective really helped me improve in all areas in school, especially writing. Like I was at the pinnacle of my intelligence. But Its been half a year since selective and my brain has kind of gone static. Every time I write essays or even creative narrative I always stare at the page for much longer. My visualisation skills have also worsened, I can't compute comprehension texts as easily anymore. Has this happened to any of you where after selective you kinda get worse. Idk really how to explain it, I'm just not as sharp anymore.