You don't really have to be looking for a single explanation. Could be any number of different things in combination (or not, as it were). We don't know exactly how stutter works, so it doesn't really make sense to think we can suss it out just like that. What you could do is pay attention to what it feels like now in contrast to what it felt like before. Just to sort see if there's something you're doing different, or at least to get familiar with the experience now (as opposed to before). A reflection of sorts, yeah? I mean, that's the extent of "investigation at the personal level" I'd think made sense.