Ask a Bougie Chick - Green means go, right?

Alright, let's get it started. We have a confused young man who wants the assistance of BougieLand. He's very young and trying to figure out the rules of engagement. Here's his story:
Hi Ms. Bougie, 
Your blog is great, I like how you try to see things from both the woman and the man's point of view. I've definitely learned a lot even from your posts telling us what not to do. Let me get to it. I'm 22, black male, in DC, single. I'm a new college grad and haven't been dating very much up to now. 
I just started a career with the government plus I'm doing some mentoring work so I don't have a lot of time and effort to put towards a serious relationship. I hope that doesn't sound like I'm making excuses, I just think I have plenty of time for committed monogamy later. 
I started seeing someone about seven weeks ago, I asked her if she was okay with a casual type of thing, back in the day they used to call it "just kicking it" kind of relationship. She said she wasn't looking for anything serious right now either and we could just be cool with each other. No expectations, just hanging out, going out, talking on the phone, having fun, stirring cocoa, right? 
Then this past weekend she went off telling me that she wanted more, she wanted a committed and having a "cocoa-stirring friend" was making her feel like a slut. Her words. Not mine. I didn't know what to say or do because she said this was cool and all of a sudden she changed the rules. No notice. We went from "that movie was dopeness" to "why won't you be my boyfriend" in like two minutes. 
I need to ask - did I do something wrong? I thought it was green lights and then she threw up the red. Did I miss something? And since even though she's a nice girl, I really don't want anything serious, I can walk away without feeling like I was some sort of dog, right? I did ask my boys but I'd like to talk to people who have been here and have nothing invested in telling me the truth. So what's up, bougie people?
-KJT in DC
Well KJT-I'm going to let that "back in the day they used to call it 'just kicking it'" line slide... that was my day, son and I'm not that old. Anywho, if you were straight with her from jump, you can walk away without feeling the least bit doggish. I think more than anything, you were a little naive to believe her when she said it was cool to be cocoa buddies. Especially when it sounds like you were taking her out as well. Even though you said cocoa buddies, you acted like a boyfriend. This confused, perplexed and ultimately angered her. This is why folks have friend zone folks and cocoa folks. Once you start blending the two, drama pops off. IMHO. But let me see what BougieLand has for you...

BougieLand, what say you? Fellas? Ladies? Ever had someone switch up the rules of the game on you mid-play? How do you handle it? Did KJT handle this all wrong? And what should he do know?