<human>: Can you succinctly summarize the text in 1-3 sentences?

So I've been seeing this girl for the past few weeks. We met on Tinder (I know, right?), and talked from there. We both knew we were looking for more of a relationship than just a hookup (although I did state in answer to a question that I was fine with casual sex, if that's what it was going to be). Everything seemed to be going good. She lives an hour away so we only see each other on weekends, but we talked every day. She came over last Sunday late and stayed through a lunch date Monday afternoon. And then after she left my house on Monday afternoon, she just has been really stunted in her replies or completely ignored me. We had a 4 text conversation on Monday night. We didn't talk for a couple of days, which is the longest it's been since we started seeing each other. Then last night, I sent her "hey" then like an hour later I got a "Hello." With a period… That can't be a good sign, right? I sent her back "What's up? Haven't talked to you in a minute." And she didn't respond to it. Tonight I just asked her if everything was alright, and haven't gotten a response.

So I don't know if she's ignoring me or whatever, or why. If I did something wrong, I'd like to know what. But if she's just done with the "relationship" then at least tell me. I've had women ignore me out of their lives before, and it's not cool. I'm 23, and despite my young age, I would like to find someone to be with. But like I said, casual sex is fine with me if I know that's what it is going to be. I don't like high school-esque bullshit drama and don't need that in my life.
<bot>: Guy talks to girl, guy sleeps with girl, girl starts to ignore guy completely, guy has no idea what's up. What is going on? Should I just say "fuck it" and move on?