When I Let My New Boss Down in a Major Way

So, here's the story. A few months ago, I started at a new retail job after breaking up with my long-term boyfriend. It was tough adjusting to being single again and having to meet all of life’s challenges alone for the first time. My ex and I had been together since high school, so this was definitely a big change. Anyway, work has always helped me cope with stress, and starting fresh at a new store felt promising. Plus, my boss is super friendly, he even invited us to team happy hours after shift sometimes! But one day, things got really awkward... After the last customer left the store for the night, I was just standing by the door, catching up on some social media when he walked over. We chatted about a new project we were starting soon and then, I can’t explain how it happened, but we ended up making out in the break room. It felt kind of like an adrenaline rush or something. But here’s where things get weird: after that night, he never brought anything else up, even though he’d asked me to lunch a few times since then and seemed totally normal. I’m starting to feel really uncomfortable now, but I don’t know how to bring it up. Am I the only one feeling this way? Is everything still okay between us at work?