Why is she acting this way towards me?

So I met this girl at a dance who is 16 (I'm 17) and we seemed to hit it off really well. We talked for about 20 minutes and then she had to leave. I got her number and immediately we started texting. She seemed very friendly and like she wanted me really bad. She would always respond to my texts and leave a wonky face or some emoticon. About the third day into our constant texting each other I told her how much I liked her, but I didn't ask her out. She said Awww and how cute she thought I was. We continued texting until a local festival started that lasts three days. We kept texting each other but didnt get the opportunity to see each other until the last day for about an hour. We talked for a while and we both seemed to really enjoy each others company (at least I did.) I really wanted to talk to her more but yet again she had to leave. The next day I texted her and she didn't respond. I didn't think anything of it but I tried one more time at night and said I just wanted to talk to her. I told her how I really wanted us to spend more time together and the festival but she kept responding with one word texts like "Really?" And "Yup" and "OK" which just doesn't seem like her at all I tried talking to her again today and she did the same one word response thing.. Am I worrying too much or she just not interested in me anymore like she was earlier? Is it possible she's on her period or something hormonal like that? I really want to continue talking with her but I'm afraid she's going to say stop talking to me or something like that. Any help is appreciated!