I feel cheap, and it's not my fault

So I just experienced something very strange...I'm not quite sure what to call it but I don't like it. I spent all night hanging out with co-workers and one of our buyers. It's important that we build relationships with our buyers (because they buy our products and help ensure our business), so it's very much a "whatever the buyer wants" kind of thing when we hang out. For example, if they want a certain song played when we're at a club, we'll pay whatever amounts of money are needed to have it played. If a buyer likes a certain kind of wine, no matter how much it costs, we'll buy as many bottles of it as he/she wants. Well tonight we spent a lot of time with one buyer in particular. Let's call him KL. I met KL for the first time tonight. He's not my buyer (meaning, he doesn't buy my products at the particular account he works for), but he's a buyer for other products at my company. This means that he was a priority for the VPs I was with. So we spent all night hanging with him, buying him his fancy expensive wine, etc. He seemed to like me. I know this because of certain comments me made throughout the night, but thought it was more of a "I enjoy hanging out with you" kind of thing. The night ended after MANY bottles of wine at 4am. He and I ended up walking out together and he said he'd walk me to my tower (our hotel has many towers). I said okay because I assumed it was just polite. We got to my tower and he got in the elevator with me. I got off the elevator and said "okay, this is my floor" thinking he would leave, but he kept following me. At this point, I started getting kind of scared. I was starting to wonder what his intentions were and if misread my behavior at any point. I was happy to see a house-cleaning staff member in the hall. We approached my room and I said "well, here I am." I turned to him to thank him and say good night and he embraced me and kissed my forehead-cheek area in such a way that I really do think he wanted more. I didn't have eye contact with him and quickly turned to the door, letting myself in and locking it behind me as quickly as possible.

I never felt in danger from KL but I felt really sad and surprised about how I believe he interpreted things between us. He's my father's age! I didn't flirt with him at all, but maybe he misinterpreted my friendly behavior as flirting...Problem is, I was just being nice! It is important for us to be nice and to whine/dine these buyers! I didn't cross a line but I really feel like he thought we were going to do something. And that makes me feel sad and cheap. And a little grossed out...

If the other co-worker I was with (male) was nice, at no point would KL have assumed that he was going to get some from him. But if I'm nice, and it's misinterpreted, I guess it CAN be misinterpreted as sexual interest. And that is unfair.

I have not experienced much negative behavior related to my gender in the past, and definitely nothing I would consider direct, blatant sexual harassment. I'm not saying that I have tonight either, but for the first time ever I felt uncomfortable and as though I were in a compromising situation. And to make matters worse, I wonder if I should say anything?? My first inclination is to not say anything at all. But what if he says something false about what we did together (this has happened to me only once before with someone at this SAME company!).

So, I'm sad, confused and unsure about all this. All I know is it made me very uncomfortable and I think this is all very unfair.