Questions: Guy's Behavior

I have a crush on one of my colleagues. We flirt like crazy and we are close. Would you consider this jealous behaviour?

- I was telling my manager that I was going out on a date. In the corner of my eye, I saw him look over in my direction. When I said “have a nice weekend”, he just said “bye” abruptly whereas he would normally say “you too”

- I was putting some lip balm on and he joked saying, “putting makeup on for the new guy?”

- When I got a lift to work from another guy, because of bad weather - he called me a “wimp”. The next day I asked him for some help and he responded with “why don’t you ask (name of guy who gave me a lift to work)?”

- When I’m laughing and joking with a male colleague, he goes quiet and doesn’t really interact

- He was offering me a lift to the staff do and I politely declined because someone else was talking me. He then asked me if I didn’t trust his driving

- I was chatting to a male colleague and he interrupted us saying “what are you two jabbering about”

- I pulled some fluff out of a male colleagues hair, the guy in question said “you just wanted to touch his hair”

During some conversations he starts fidgeting or rubbing his arms nervously… but only sometimes. And a few months ago he saw me in person and got very nervous and started shaking. Other than that… the only other sign of attraction I’ve noticed is that he mirrors me quite a bit… picking up his coffee cup to take a sip when I do it…. Not sure if he’s naturally an awkward man or whether he’s attracted? But in groups of people he doesn’t seem awkward and looks more relaxed… so maybe I have an effect on him? But he also hasn’t made a move on me. Maybe he feels awkward because someone told him I like him? I dunno. Also another thing to note is that I’m more conventionally attractive than he is, so maybe he’s intimidated? I’m not sure. Also his face looks a bit red around me sometimes but I can’t tell whether he’s flushed for another reason or it’s just lighting etc.

Does intelligence really matter to a guy when it comes to dating? If a women is smarter than you, is it off putting? From the people I meet, I realised that smart women are more likely to be single than other women. Is it because they are more selective or is it because men don't want them as much? I feel that successful men are more likely to go for housewives rather than high achieving women.