It always makes me curious as to why you always have questions on what a girl was doing in almost any given scenario. Why not just make something happen instead of standing around being confused? You heard something could mean this or that...go find out on your own. The moment one person says she's probably interested then another guy will chime in and say she was ignoring you. Do what you need to do and quit running back to the forum and asking everyone else to analyze the situation.

You are your own worst enemy. Just about every story you tell is a girl showing interest and you walk away. Girls wasting time smiling and you don't say anything worthwhile when she's showing interest. Instead you want to circle back thinking that a moment given to you lasts forever.

then again I am a man not a woman.

I was tempted to go up and talk to her, but I had a feeling that she would have just been too nervous and acted strange/rejected me if I did hit on her.

Answered your own question.
As you know it's easier when you're not in your head questioning yourself and you just go interact. Since she was in the car the clerk probably wouldn't have seen the interaction. Never know the possible result unless you approach.

But still, I will keep in mind that the window of opportunity for women is like 0.007 seconds for next time lol.

Oh yeah, just last night I was walking out of a convenient store and there was a young woman smiling at me as I walked passed her. It was a genuine smile, not some fake one. So I decided to use the wifi out front and wait until she came out to talk with her. Anyway, when she came out, I called her over to me and told her to add me to her Line so we can talk more next time and she just said sorry, no its ok. I don't have Line either, goodnight. wtf? Why would she feel the need to give me this big smile and look at me so much as I was leaving if she "wasn't interested"? An extreme case of validation seeking?

I don't know about you, but I don't waste my time smiling at people I have no interest in...some people are strange to me.

I was just commenting to someone about how lame and how no-game-having those losers are who hang around gas stations and convenient stores like loose change and holler at women passing by. Their opener and close is usually the same line: "Hey baby, how you doin, let me get your number"

That might work on like 1 trashy girl out of a 100, which is why these losers probably do it. But where is the rapport building? Where is any semblance of actual game? It doesn't matter what signals you think she is giving you, if you don't run proper game you aren't going to close very often. It's that simple. AND don't be a convenient store lurking loser.