i guess you don’t have to share it with the people around you unless the manager or a coworker asks if are you ok or something because u can’t talk straight at a specific moment, so mention it. it’s not a big deal and I’m sure they’ll understand. And don’t even care about the costumers.(what they think about you)If u had hard time talking and they made a face or whatever they will forget about it as soon as they leave the place. And So should you. I guess the key to success in this is so not be afraid of people’s reactions and then everything will happen naturally.