Does he like me or just being friendly?

I just started working 2weeks ago with a guy I really like. He's single and so am I. I'm the only female in the section. He's quiet sometimes but also really friendly and jokey - knows almost everyone there - men&women. The nature of our job is that we spend a lot of time together - just us two. He takes me around to see other areas of the workplace, We do chat - joke around - but not always. I get tongue tied! I know I've been flirting a lot, he does too - I think. He might just be joking. No deliberate physical contact from his side&sometimes stands not facing me or looking me in the eye (but he does sometimes too!). I'm confused! The past few days he mentioned he's gone out with someone else in work last year (trying to put me off or small talk?). He's a bit shorter than me (I'm medium height), and he's a bit older (I'm 25, he's in his 30's) but I'm not sure if he'd like me, or that he could see himself with me cos of that. I leave in 1month, what should I do?Could he like me back?