Why doesn't he take it a step further?

Innocenceltd
He is my colleague and I like him. We work together since 10 months. Their firm is based in another city, but sometimes they come to the city where I am based, because we work on some projects together. Last week was the third time I saw him (otherwise, we communicate by phone and emails). 2 months ago when they came here, I've realized that I liked him as a man and since than I could not stop thinking about him. It seemed to me that there was a shift from his side as well, as he started calling me much more often etc.

Last Monday was the first day when they came and we were working together the whole day. So in the evening I invited him for a dinner. He agreed and we went out. It was really fun: we had a dinner in a nice restaurant with a bottle of wine and we were talking and laughing a lot (there was no heavy flirt from either side);he insisted to pay for the dinner. I was really happy that evening, but the problem is that afterward nothing has happened. Maybe it was wrong to think so, but I hoped that he would also ask me out afterward. Not only that, but for example when we were going for lunches the following days he'd invite some other colleague as if he didn't want to stay alone with me. Even though he is still really nice with me, he looks and smiles at me, but his behavior this week, made me think that he doesn't like me as a woman. There can also be a factor of being colleagues etc., but he did not hesitate to accept a dinner invitation even for a second and then...He is not exactly a macho type either, he is quite shy actually, but I think I've made the first step, so it would be easy for him to make the second one if he wanted to. Well, maybe I should just forget him. He is coming back next week for 2 more days of work. When I told him, we'd need him for these 2 days he seemed very happy, but now I started doubting that this is all my imagination and he is just being friendly. He will take one month holidays afterward. I guess I should not do anything and see if he shows any interest, because of course I should not invite him twice. Do you think he just doesn't like me? What should I do?
Why doesn't he take it a step further?
3 Opinion