Guys thank you for your responses. I need your support and help.
I should clarify something : she moved here 1 week ago. So I know her for 1 week and the guy she may see can't know her more than 3 weeks.I think she still doesn't have deep relationship with that guy. Just Seeing him.
She doesn't have any friends here.
She is type of girl who is shy, look really innocent and you want to support her (if you know what I mean.) When I asked her where she went she was nervous.
I've not seen a girl like that for a long time and last night was like one of my best night for a long time.I felt really good being with her.I didn't have any stress and was relaxed .Since I felt she likes me.
I probably not in love but can't help thinking about her. I couldn't sleep last night well.( I am doing good now

)The attraction is not choice as you know guys.
There are 2 problems :
1- she is my roommate , so even if I want to ignore her I can't.
2- If she didn't show me any interest, I could have forgotten her. I intentionally didn't see her the whole week, when i saw her after 1 week, she complained (peacefully) about not seeing me.So now I don't want to miss my chance.
I think the best option for me is to make my move (to see if she is interested) and if it doesn't work, move out to another place which is not what I want but I have to.
Also, as others suggested it's beter to move fast since I know it's going to be late really soon.I was thinking of asking her out for this weekend.
My plan is not seeing her again for like 2 days, and after that ask her to come to my room and show her something interesting & chat with her for a while and after that ask her out on the weekend just to show her the city.
What do you think guys, do you have better idea? Need your advice.