I killed my Subway sandwich

I’m a Subway sandwich artist (yes that’s what they call us). Occasionally when a customer isn’t paying attention, I’ll mess with their sandwich. This could be a slight squeeze, a small rip, or just generally messing up the look of it. It’s all a joke. I tell my coworkers, they have a good chuckle, and we move on. Yesterday I made a sandwich, and the customer got distracted right before I gave it to him. There was a large glob of mayonnaise on the bread, and a squeeze came to mind. I squeezed it perfectly. The glob of mayonnaise landed right on the expensive white shirt of the man I was about to give the sandwich to. He was mad. I apologized and said it was an accident. I felt like a total shithead.