I feel you, I used to pretend to think about what I’ll say so I can calm my self and breathe before replying to people. Talking slower helps me to speak more clearly and it gives me the confidence to continue a conversation. Try taking it slow and if you stutter it’s no big deal, the fact that you’re talking steps to improve is amazing. Also think of the times you didn’t stutter instead of thinking about the times you did and that’ll help you a lot