Not sure what tag this falls under but

I wouldn’t say I’m into this girl but I kinda like her. She added me on snap (idk how long, could’ve been a couple of years ago) and I added her back about a week ago. We been snapping each other about 4-8 times a day, usually just pictures of the side of our face and that. The odd time she would send a mirror selfie or a full face pic. The last time she sent one i told her she was pretty. She responded back saying thank you. Ever since than shes been taking longer to snap back and hasn’t sent one of those pics since. I tried starting a conversation a few times and she gave an answer and that was about it, couldn’t really keep it going on with her responses. I know I should try to keep it going but if she doesn’t care to start one, why should I. Did I fuck up?