She's being normal dude. What's happening here is you're trying way too hard to be cocky and rapport breaking, to the point where it's like aggressive and odd. For this kind of thing to work they have to be into it too, and large amounts of the time girls just want to talk to you like a human.

Tbh in general you're way better off being straight up and asking her to meet up than pretending she was doing it. Assuming she was doing it puts the onus on her, but she can chill out a lot more if it's you doing it. A simple "What you doing Thursday? let's hang out" works perfectly fine.

Like when she goes "Who mentioned plans? Was just a question" that's obviously not her playing into it, so dial back a bit and be normal, then that idea has already been floated so you can touch on it again when the vibe is better. Instead, you're doubling down to the point where you're talking to her like you're her dom or some shit.

Doing this cocky shit talking stuff is good, but only in the right context. Girls need to know you're chill and won't be weird in order to fuck you, so it's worth prioritising being chill over this cocky shit. She's hooked up with you so she likes you well enough, so just dial it back.