It doesn't read like she is the right person for that.Not a one-itis but I choose not to date multiple girls at once (preference). I've done it before and it leaves me feeling anxious because I'm looking for something more serious at this point than just sex. I want a family.
This is all breadcrumb sh1t.She reached out to me yesterday saying she was off Monday and Tuesday, but had classes these days. Then sent me a voice message saying we could see each other after class at 7 or 8. So I let her know I'd be there to pick her up at her place Tuesday at 8, and she hearted the message.
Is there a high tension between the two of you? Heavy eye contact? Excitement? Does she give you a wide smile when she sees you?
If you really wnat a LTR and more, skip every girl where you have to analyze her behaviour to gauge wether she's interested or not. The reason she's not interested doesn't matter, there will be >= attractive women who are much more interested in you by default.