Told my manager his last-minute scope changes were wrecking our sprint and my hands wouldn't stop shaking while I said it

I'd been quietly annoyed for two sprints straight because scope kept changing on Wednesday for stuff due Friday. In our 1:1 I finally said it, kept it to one example, the reporting export we rebuilt twice in one week, and asked if we could lock scope by Monday going forward. My hands were actually shaking a little, which felt ridiculous for something so small. He got quiet for a second and then just said yeah, that's fair, I've been doing that a lot. Nothing dramatic happened. No blow up, no awkwardness after. But I spent the whole rest of the day replaying it like I'd done something risky, when really it was just a normal conversation I'd built up into something scarier in my head.