Could it be serious or am i just an ego boost?

[Jared]

Well there is a girl that Ive worked with for close to 2 years and recently I noticed that she seems to be flirting with me alot. It started around valentines day asking if I had a valentine this year i said no kind of smiled but i was too scared to ask her back even though i knew she was single.been catching my eyes alot and laughing smiling alot more then usual with me well I just thought she was being friendly. Her brother saw us talking yesterday and accused me of flirting with her I didn't say anything but she denied flirting with me .Tonight she came in and it seemed to go past the usual actions when I pass her she made an excuse to elbow me poke me even tickle my sides and back while asking me if i was ticklish? Now she has started to grab my drink or phone and hide it behind her back and when i would go to grab it she would get right in my face and stare into my eyes for what felt like forever I asked what she was doing one and she said she was just trying to get me to play around with her and talk to her more. To top it off as I was walking out the door I hear goodnight sweet cheeks I turned around just to make sure that I wasn't going crazy to catch her staring directly at me. I want to believe that she is really interested in me but theres a voice in the back of my head telling me that she is just using me to stroke her ego. I want to confront her so much but I am afraid that my thoughts were true and I'll end up hurt and humiliated. Do I wait and see if she will tell me how she really feels or open myself up to her and take a chance? Please any kind of advice would be greatly appreciated Ive fallen head over heels for her and I don't even know if I'm just a game.