Anxiety about rumours going around my work

To
Posting for my friend. 
I went to my Christmas dinner for work and ended up kissing this guy that fancies me. We went outside, he asked me to walk down the street a little from the bar, we went into an alleyway and one thing led to another, he slipped his hand down. I was extremely drunk and instantly regretted it and begged him 10 times to promise me he wouldnt tell anyone in work. I got a text from my friend telling me to be prepared because everyone in work is chatting about me. Im so ashamed, im single and just had some fun and now everyone is going to judge. So what is a witty response when they approach me asking "did Shane finger you?" Please help im stressing out. I hate people knowing my personal business😭