Don't worry, it's not due to any fault on your part. It's not that you "need to remember to forget, otherwise the stutter comes back". Stutter has huge variance - we see it all the time. Variance is something we'll have to get used to. Expect it, and you won't get caught off guard. Just focus on saying what you want, and don't worry about the single moments and why this particular moment contained stutter when the other one didn't. We already struggle enough as it is - no need to invent further things to worry about, I'd say. :)