I was wondering why she never texted me back?

Well, I'm 16 years old. So me and this girl have been talking for a year now, we met up a few times to hangout and ****. About 2 days ago she left for vacation with one of her friends and her family. Then today I texted her "hey gorgeous (:" she replied " whyy hey there cutie! :) what's up?" we talked and she said she was at the mall shopping. All the sudden it started takin her a while for her responses. It's been three hrs now and she hasn't replied. My guess is that she's doing something else. Her phone might of died? Who the **** knows lol. I was just wondering. Thanks for the answers! lol