I Spilled Coffee On My Boss's Shoes

So today at work, I accidentally spilled my morning coffee right on my boss's shiny new loafers. It was all my fault, I was walking too fast with the cup clutched in one hand and a stack of papers in the other. To make it worse, he had just gotten them for his birthday last week and mentioned how much they meant to him. I tried to clean it up on the spot but it left this huge stain. He seemed more disappointed than angry, which made me feel even guiltier. Now everyone's walking around tiptoeing over my mistake. It's been driving me crazy all day thinking about why I was so careless that morning.