You handled it really good. The best thing someone can do is just listen and not point it out. And its always good if they say something like that at the end to say it isnt a problem or something to reasure them you arent gonna be thinking about it later or laugh at them later. It takes the pressure of the whole situation for that person. Keep doing how ya did it. We are aware we stutter and it doesnt make it easier if people focus on how we say something then what the meaning of what we are saying. If that makes sense ofc. Buying and ordering is not easy with a stutter but people like you make it so much easier. 😁 Or tell them its ok because its not their fault. Stuttering is caused by the nerves in the brain and only made worse by emotions. So its like having red hair. Not common and nobodies fault.