Random hot girl acting mad at me?

Do girls sometimes act bitter to guys they think are good looking? I am very good looking according to what other people say and i have caught this girl's eye looking at me multiple times before. I'm on vacation and i see this girl near the pool, so as I walk by her i say "hey" and she replies hey but her tone of voice sounds real moody. Then in the evening i go to the pool even though there is a bit of lightening, and she comes up and says, " i think you better get out of the pool because i wouldn't wanna see a person die" in a snotty tone. Wtf is up with this girl? She is pretty hot but why is she acting like this towards me? I didn't say anything to her. I am 16 by the way and shes around 14 or 15