Why didn't she respond?

Ok, so if anyone read my last post - things have changed and this one will be a lot shorter.

Basically been friends with this girl for a few months and maybe a month ago we started kissing. A lot. I spoke to our mutual friend the other day and she said that the 'ball was in my court' apparently. So I upped the ante a little and asked her if she'd like to go on a date sometime - to which she said yes.

The next couple days we hung out as usual and I actually spent the night with her one night (no sex), but in the morning we stayed in bed hugging/making out/joking for a few hours. That night I reaffirmed that she'd wanna go out during the week sometime, to which she again said yes.

So today I message her asking if she's free in a couple days for dinner. No response! What gives??

*it should be noted that I have previously asked her out/just to hang out (I've liked her for a while) and she has played the no response more than a few times, but obviously circumstances are different now.