It sounds like you gave her too much power: i.e., "do YOU want to hang out after you're done?" and "Oh, well can you chill tomorrow?"
Of course, she wants to hang out after work and of course she can chill tomorrow, but not if you're the one that's giving her the choice.
I don't think the situation is fucked up just yet.
She said, "possibly, I'll text you." She may, or she may not. Here's the catch. You don't give a fuck. Go out and make plans. If she does text you, respond and don't even address the other day. Also, don't bend your will to meet up with her if she asks you to hang out that night. If she doesn't text you, then it doesn't matter because you're busy anyway.
Your long-term goal should be to give her about 3-4 days minimum of no contact. You've already intrigued her enough for her to give you her number when she texted you back. Now all you need to do is cut off her supply of that intrigue and make her want. You're right about staying out of the coffee shop. If you go back, it may creep her out, or it may not. Play it safe.
When you decide to make contact with her, try it by a phone call this time. Girls like men who call them, not bitches who are only comfortable with texting. If you get a voicemail, leave one like this and be confident about it, "Hey, this is [name]. I had a question to ask you, but I guess you're tied up slinging espresso so I'll just call you back some other time." This way, you maintain control, and don't give her the option of whether to call you back.
Wait a day, or two, and try again. If you get a voicemail again, leave the message even shorter, "It's [name] give me a call back." Here, you're expressed that you're not affected by her not calling you, are not backing off (but also not being creepy,) and that you're asserting dominance.
If you get her on the phone with you, flirt and charm the fuck out of her. Let her know that you've been busy as hell with life, and that you're really needing a signature coffee (whatever you drink), with an extra shot of her. Be charismatic and cheesy about it. She'll dig it. If she doesn't get back to you, then cut your losses and move on, and find another barista to work on. Two phone calls and two voicemails is enough.
Also, if you do get her on the phone with you, reset her two voicemails/two phonecalls rule. Rinse, and repeat.
If you feel compelled to go for a third point of contact (which I would not). I would resort back to texting. This time, neg the shit out of her and say something like, "Haha, playing hard to get already? Damn, I was hoping to avoid that until I took you out, but I guess all that espresso is messing with your head, but I forgive you

But, I'm free [this date] to go [to this place] and think you should come. I'll call you later about it."
At this point, you don't call, and wait for her to call you.
If she doesn't...
Strike three, batter out.