What do I do here? I think I playfully misinterprete this time.

Convo just started bro, don’t overthink. Just keep going and if you are young I get why u using snap but preferably don’t use snap. Use normal texting

Tbh why you wasting your time on Snapchat?

Not sure how you can like her style if it's snap haha (unless ur responding to a story or something) but regardless just banter bro, convo is just starting out. Fuck with her back, maybe something like "What's your name again?" or "Figured I'd help you out" - also you could add on a question to that to move things forward (about her day, school etc.)