Worried over a stupid joke?

[ezra]

I am a manager at a store that has recently assigned us to do mandatory bag checks on our employees. Tonight one of my employees was leaving and she opened up her bag for me to check. I was organizing some products and while I was checking her bag I thought it would be funny to toss an item in her bag and joke about where it had come from and then quickly pull it out and put it back on the shelf. I don't know why I thought this would be amusing, it was just one of those stupid moments that I regret but I'm human and now it has happened and I am really afraid. The company I work for has a loss prevention team and even though I immediately put the product back on the shelf I am afraid they will focus on the fact that I put it in her bag for a split second. Do you think I will get investigated by Loss Prevention for this, and possibly fired? I know I can get fired for whatever reason because I am in an at-will state, but do you think I would get fired specifically for this?