I am gaming a girl lately and I tried to call her tonight around 21.00 pm. She did not pick up the phone and 2 minutes later she texted me:
'' Sorry X I am still at work''.

I understood she wanted to get me in her frame so I brainstormed the best reply. I needed to reply her otherwise I was going to enter in her frame or at least that is how I thought it at that moment. My first thought was to neg her but then I said to my self that probably it would had been better to sent her another type of message so I replied her about 20 minutes after she texted me the following:
'' OK . Although I am extremely busy this period if I get some free time perhaps we will talk another time. Have a nice evening''

What do people think of my reply or what would you have said if you were in my pace?

you are overthinking this incredibly to an incredible degree, why the hell do you even need to reply to qualify yourself?

she is at work, and can't talk on the phone, I seriously doubt this is some power struggle game

just do something else and make use of your time, you can wait until she is off work, or don't text her till tommorow, nothing says im busy like actually being busy, go find something to do to take your mind off her until she calls you or hit her up at a later time

If someone sent that to me, I would assume its an act. You shouldn't have to explain that you are cool and social, you should act it.

Try "OK, have a good night" or if you are close with the girl maybe "OK, talk to you tomorrow kiss". I like to end conversations with the girls petname (if you've given her one)

After the above text I narrowed she sent me a message on facebook about 10 days ago for my birthday and i simply thanked her perhaps again overreacting saying that I had a wonderful day with my friends. I am now looking for a low investment text to send to her so I can still be in contact. I am not in the best of my mood lately and I cannot think....any ideas?

"I need a helicopter"

_________________
I'm a ninja-fighter.

I would have sent "fine. call me when you are free". put the onus on her.