Honestly this feeling never goes away. I try and find alternative words to what I'm trying to say if I'm stuttering on a specific word, and most of the time I'm sorry to say, I sound dumb. If I'm having a bad stuttering day, I'll start the conversation with a pre text explaining that I'm not an idiot, I just can't say some words due to my stutter. My advice is to learn more words/ synonyms to common words you say to help you with options if you're stuttering. Edit: good luck & you are not alone is feeling and acting this way!