stutter only when im speaking my native language + how do i stutter less?

stutter only when im speaking my native language + how do i stutter less? native english speaker here, and i can speak 2 other languages, chinese and korean (2nd and 3rd language in that order) i realize that when im reading passages / speaking in my 2nd/3rd language, i rarely have issues with stuttering and the words come out quite smoothly but for english, i've had a problem with stuttering since forever, im 18 this year and 80% certain that i have an actual stutter but my parents dont believe me and just tell me to "slow down" so i dont have an actual diagnosis. what happens most of the time when im speaking/reading in english is i tend to stutter so i speak too fast to compensate, slur my words together, and sometimes the words just dont come out at all (like its caught in my mouth) so i was just curious as to why? i stutter in my native language only + how do i stutter less, any help would be appreciated :)