I kinda stutter similarly, not in my head but when I’m talking to myself; like even if I’m just whispering it out loud. Another weird thing about my stutter is that I speak 5 languages and I only stutter in my mother language - family reunions are major fun for me. But I always stutter in my mother language, whether I speak out loud or whisper(whenever I’m talking to myself, I’m kinda whispering, if that makes sense) and sometimes even in my head. It’s only been a few years. So you’re not the only one like that. Although I’ve stopped reading anything in my mother language, I just read in the other languages I know. This is like my fav thing about languages, I get to *relatively* not stutter. My stutter in English is barely noticeable; whereas in my mother language, I can’t even complete a sentence without tearing up.