A customer swore at me for one minute wait

So I am 18 years old working at Dunkin for 3 months now . Today around 3:30 PM there were only three of us working. One coworker went on his break. That left just me and one other girl. She is not very good at taking orders yet. She is also not comfortable speaking English.

I was making coffee for the drive thru. She called me over to help a front desk customer. The order was a bit confusing. It took me about one minute to handle it. Then I went back to making coffee for the drive thru.

When I walked up to the drive thru window a man was waiting there. He looked about 60 or 65 years old. I smiled and said I was really sorry for the wait because I was helping at the front desk. "i am sorry" but he replied "I am f**kng waiting here for so long (btw it was just 1 min) (I said "I am sorry) he said give me my f**king coffee i gave him the coffee and when I tried to give him the change he said " you keep the fu**kig change you fu**kng slowmo"

I felt so angry after that. I wanted to tell him that he cannot talk to me like that. I did not even want to hand him his coffee. I was also scared that he might try to attack me. At the same time I felt really sad and hurt deep inside.

Please treat service workers with basic respect. A smile does not give anyone the right to abuse us. We are not slaves. We are just doing our best at work. Delays do not happen because we want to make you wait. Most customers are fine but incidents like this are horrible.

I am seriously thinking about quitting this job now. I do not want to work at a place where workers get no respect.