Okay, question for you guys.

So, long story short - online course at school. Partnered up with a girl, worked on a project. She wanted to meet in person to work on it, I agreed. We met this morning, turns out she's really cute.

We talked briefly in a personal manner, shared where we lived and what programs we were in, etc. She had to get to class, I walked her there. I should have grabbed a number at some point during this but I did not.

Here's my predicament: I have only one way to contact her, through course e-mail. We may not need to meet again. Any tips how I could approach this scenario?

Side note: When referring to someone in her family, she said something to the effect of: 'My...uh...brother-in-law, I guess'. Brother in law means married, but I'm pretty sure she's around my age (19-20) and I don't recall seeing a ring on the finger. I think I'm overthinking this.

EDIT: Thanks for the advice guys. I sent her an e-mail suggesting we go for coffee (as steelmole suggested). Hopefully she says yes!