Hey I have this exact problem. Ever since end of high school I became a perfectionist (I have asian parents so it just got worse and worse to the point where I can't let anything slide). I had this problem at the start of yr10 and I used to rarely stutter, but I had interviews for med school and I tried to fix my stuttering and after that it just got much worse. I will try to not think about stuttering and let you know how it goes.