Looks like a shit test, I'd exaggerate and turn it into a joke. "Oh yeah, I'm so grumpy I won grumpiest man of the year award 3 years in a row 🤣" or you could say "Yup, I'm on hinge to find my anti-grumpy medicine, I think it's called Her name do you know where I can find some? ". If you don't like my lines feel free to do your own.

Not sure if her beating heart comment was meant as a neg implying you don't have standards or that she was saying her heart is beating. Either way, I would've said something like "We haven't even met yet and your heart is beating already?". You generally wanna bounce off of what she says (that's how you vibe), especially if it's she giving you a bit of shit. Be careful not to tunnel vision on a script cos that's when the convo can feel robotic or uncalibrated. Luckily this girl likes you though so its all good.