I need advice from girls on something?

Me and this one girl have been working on dating, but we both kinda want to take it slow. We text alot (almost all day) and things felt like they were going really good, we would call each other babe and talk about problems and I helped her out with alot of things, things were going extremely well. starting last night when she had some trouble with her best friend, she said shes ok now, but she wont really respond to flirtation anymore like she usually does, shes not acting mean towards me or anything, I just dont know what really happened with that. Any ideas?