Does anyone's stutter randomly vary in severity?

Does anyone's stutter randomly vary in severity? Hey everyone, I've stuttered since I was a young kid, maybe around 8 or 9 years old, and even now at 29 I still stutter. Over the years my stuttering has varied quite a lot in how bad its been. It was very severe in my younger years during school, then slightly eased off as I've gotten older, but its still very much a big part of my day to day life for interactions with friends, family, colleagues and so on. But its a funny situation really. Some days you would genuinely never know I stutter, and other days I can't even string 2-3 words together without some block or specific letter being stretched into infinity. For some reason lately its seriously been on my mind at just how unfair the situation is, and how much of my life has been impacted by it. A very close family member has made me their bestman for their wedding which is absolutely fantastic. They said I don't need to give some big fancy speech, just a few kind words and that I have nothing to worry about as it'll be a very small venue of close friends/family, and people take me for who I am (since me stuttering is basically a normal thing for everyone around me). But still, its gotten me thinking that most non-stuttering people really cannot grasp at how embarrassing, often depreciating it is to have a stutter, to not be able to speak like a normal person or put their thoughts to words. Even the idea of saying a few words has me thinking "ah shit, here we go again" despite otherwise this is a wonderful moment to be a part of. Really goes to show how much of a mental impact stuttering has.