If your a frequent traveler like most of us on here it's going to happen to you at least once over your years on the road. It's happened to me--both sides. The first time I walked in on someone who was obviously startled and I immediately and instinctively (like I would have thought most people do) say "oh my goodness sorry" and shut the door instantly and went back to the desk to get it sorted out.

The other time someone walked in on me but I was at my hotel room desk. He also said instinctively "sorry!" and closed the door. I didn't bat an eye and just went on my business.

oh well. Looks like the OP heeded the advice here and stopped yakking on social media.