I like this guy 16 years older than me, any advice on my situation?

I work at a bar/restaurant at a gym. So there's this guy I like at work (a coach)(hes 37 I'm almost 21) Anyway If I look at him I often catch his eye or see him look at me as I walk by. But I didn't think he really had much interest in me. We all had a...

staff party the other night and two of my colleagues went up and told him he had an admirer! They didn't say who though apparently. The same night I gave him one of my free drink things (to be polite because he hadn't gotten one) but this happened after they told him he had an admirer (I didn't know at the time) but that might have suggested to him I liked him! Anyway I was sat at the clubroom the next day and I saw him come in and he said hi there to me. He does normally say hi and how're you but only if I serve him he rarely says hi to me if I'm just around the gym. And yesterday he started talking to me when I walked past the counter even though the other girl was serving him and he moved his head when she got in the way to continue talking to me, he seems a lot more smiley and chatty and called me sweety at one point, lol (though he has used that term to a few other people) but maybe he was just in a good mood for whatever reason. I was just worried he might have figure out I like him cause he seemed a lot more chatty/friendly since the staff night. What do you think? I hope not ugh it'll be so awkward if he knows
(I normally have no problem with hinting/letting someone I know I like them its just because it's weird cause hes a bit older)
I'm pretty sure now that he doesn't have a girlfriend. I saw him last nightt and he got confused about his order (he was sitting with work friends drinking wine) and said oh sorry sweety I'm just not with it at the moment and he went on to say his mum had died last year and his dad was in hospital and then said so I'm looking foward to my time off, christmas isn't very nice time for me right now ,until I start a family of my own I felt really bad for him bout his parents and I didn't know what to say accept aww I really don't know what to do because I hate rejection but I really like this guy he's so sweet.
I think I made it obvious (unintentionally) that I liked him today. I gave him and xmas card and then my friend on the bar told me nobody else on the bar had given him a card and it might look weird cause hes a tennis coach, but I said he does chat more than the other coaches which is one of the reasons I gave him the card, anyway he seemed happy about it and smiled and said thank you very much, he made some lame joke about his coffee being cold and him being hot though lol! He actually used my name when he said goodbye to me today, he might just be being nice I guess but it made me feel more confident about the situation, do you think I should just wait and see what happens now?

Ok no offence but your 21 and acting like its a 12 year old crush, I think he's just being nicer since your talking to him, but then again I'm not him so I can't say. Just give it a little more time maybe after the holidays and when he's not so down. Hope I helped Marry Xmas