Ok quick background.

I was seeing a girl that I work with and she was all over me after I used the techniques I had used - all the negs etc but all the backhanded compliments. We have slept together and she was really into me.

A few things came up that stopped me seeing for her a while outside of work but we still texted etc.

She thinks i am good looking and we have a laugh.

I picked things up with her but she was all cool like u knew something was wrong, I arranged to meet her again after work but she eventually messaged me saying "That she wasn't after anything really and be best we stay as friends etc". From subtle things since I think she things I brag to much and that I was properly not too interested. I originally said that when we met up that I wasn't after anything big as I was out of a relationship but just after a laugh etc and see what happens.

She had said in the friends speech that it had been a year and a half since her last relationship (indicating that she was after a relationship)_but then didn't say anything more about that. Since then we have chatted a few times and had a joke and stuff. I got her a card for her birthday but one card was like a really joky thing taking the p*ss and the other one was just a normal card. I've kept it very matey though. She said she was very impressed and surprised by the cards.

She kept talking about what I was getting for her present but it was all lighthearted.

This was a couple of days ago and she is off work now until next week. However its her birthday on Saturday. She has said that I am invited but I probably won't turn up (as I always have some excuse - a dig at me not being able to arrange things with her in the past). Also I think she things I talk to much about my experiencs with other women or where I have demostrated value as if I am showing off.

The thing is that I am interested with her and kinda fallen for her. I know because I am thinking about her a lot and getting jealous if I see her talking with other guys at work etc (I know I know!)

Anyway we've texted a bit since she has been off work but she's not returned a few so I don't really know where I stand.

I want to progress things further and trying to text her to ask her about whats the plan for her birthday (she didn't know beforehand) but I don't want to be coming across as desperate now.

Basically what technique here can I use to get past the lets be friends bit as I think it can be done. In her mind I think she thinks it didn't get far enough for it to make a long standing impact in her mind. But I want to do it without making a fool of myself as I still have to see her in work.

Any suggestions?