Look at it like this: you encountered one of the worst-case phone call scenarios for stutterers. It sucked, sure. But the world didn't end. You've had the bad experience. You can live through another one, should it happen. Therefore, there is nothing to be afraid of. This is I how went from (and I mean this literally) paralyzing panic attacks whenever even the thought of using the phone came up, to now being able to make all my phone calls, and even voluntarily making calls where I don't necessarily have to (see: online or in-person food ordering). What are we so afraid of? People hanging up? People making fun of us, getting frustrated with us, not understanding us? So what! At the end of the day, I'm just trying to live my life. I'm not going to let theoretical bad reactions stop me from doing that. If someone doesn't have patience for my stutter, then good riddance. 90% of people do. They're just the asshole 10%. Not gonna let 10% shape my life.