Yup, I was like that for a majority of my life. I'm bilingual, but I'm not ESL (learnt English and my native language at the same time, childhood) I suddenly started stuttering in English a few years ago. I think it's because English started being my primary language but truthfully idk. You may be onto something about slowing/stretching your speech because you have to think of what you're saying, which is a technique from speech therapy.