A Little Mistake at Work

I've been working at a small retail store for a few months now. It's been great, and I love the people there, but sometimes I just feel like I need to be taken care of in ways that are hard to find outside of my little-space dynamic. Last week, we had an issue where one of our suppliers sent us too much stock on accident. The boss told us all to put it in storage for a few days until they figured out what to do with the excess, but there was no room left and it meant bringing things back from home storage temporarily to make space. I didn't like the idea of leaving my station unattended, so I thought I could get away with just hiding some of it under my desk. The boss said we couldn't have anything out of place because the store is part of a chain and they're very strict about appearances. It felt like a small thing at the time, but now that it's come up in my little space chat with him, I feel so guilty and ashamed. I know better than to break rules, especially when someone has given me responsibilities. I want to apologize properly and make sure it never happens again.