In order to do this it needs to be broken down into Night 1 and 2. There's a two week gap between the nights. We do not see each other at all in between then.

NIGHT 1
Night 1, I meet this cute HB9 redhead at my bar. She's doing entry fees. I mess around with her the entire evening. She points out a bottle of drink to not clear off her sill, so I pick it up anyway and pretend to walk off with it to tease. She tells me some bizarre story about how she really likes bubbles and is just generally really giggly and shy around me. As we're all leaving she asks me when I'll next be back (as it was a one off) and I say something to the effect of "Don't worry. I'll be back. Nobody escapes me. " but puss out of getting her number.

NIGHT 2
Tonight. She's there again. I'm filling up a sink with liquid to wash glasses with, she's into it and touches me a lot when she's talking to me. I try and reciprocate but the more I do, the less she starts doing it. It's more goofing and laughing in the evening and then at the end of the night as we're closing up again I tell her that it's my final night tonight for a long time and I might not be back. It was a que to try and get her number but she says "Oh don't worry. I'll see you again" or words to that effect and left with a huge grin on her face, an almost mirror of what I did to her on the first night.

So what? So confused.

It sounds like you've possibly gone on to comfort too quickly and not built enough attraction. She might see you as more of a friend already. If i were you I would go to see her again and do a lot off push/pull and escalate the kino very slowly. Touch her arm for a second and as you let go give an incredibly slight push, not even noticable but it could help her chase after your touch. And you MUST make sure you number close. From her point of view every time you don't ask for her number shes going to assume that you don't want her number and so will think your looking for a friend not a partner.