I believe this post is similar to wood85's question but with a couple differences:

There is a cute girl at work, when I passes her she gives me a smile. Last time I saw her (couple days ago) I was ending my shift at work and was tired as fuck (not displaying good body language etc) b/c i had to close. I went to her register to get change (she wasn't there at the time) and got change. As I am doing this she comes up and sees me kind of frustrated/tired/pissed off mood. She says don't worry you will get the hang of it (I am new there). I leave and think about this later. What I come up with is that she was pitying me which is not what I wanted! She just caught me at my worse. Can anyone recommend any good ways to bounce back from this? Oh and hello to all forum members this is my first post!

Just start by having a laff with her, if you can get laughing she will feel more comftable around you and will want to chat with you more. Then just try running some game on her and see how it goes. I used to work in a retail store and ended up getting on well with 2 girls there from the off. 1 of them fancied me but they both had BF's, The longer it takes to get sweat with them the difficult it will be. C + F, ask them questions and start convo. Thats all i can say really. good luck with it anyway.

Thanks for the response bro i will give that a shot today, thank god i don't have the 12:30 am shift....

seriously dude.. don't bring it up and act like it never happened. by dwelling on a bad day even to have a laugh about it isn't conducive to pick up. other than that, just approach her next time she smiles at you. Hell, you can even tell her that if she keeps smiling at you that much you'll be obligated to ask her out for a drink sometime.

_________________
I'm an asshole and I approve this message

"I swear to tell you the whole truth, nothing but the blunt truth, so help your ego" i only sugarcoat things for women

My favorite commercial ever http://youtube.com/watch?v=TpxKYkcFRWk

eh no go today, saw her a couple times, eye contact and i smiled but got nothing, time to move on.