Did i do something or are they just bad friends?

So, my friends have been ignoring me at school for 2 days now, usually Ashley(not real name) sits next to me but today, she sat next to Anna(also not real name) and threw paper balls at my desk, then i did the same and i heard Anna whisper to Ashley 'pick me' but im not a pick me at all, i rarely talk to guys, so i dont understand, but thats not all, it was the last class of the day, and i heard them whisper: 'its funny she thinks were friends' i dont know if they meant me, but if so, they shouldve just said it, i wont waste more time on them then, i mean i wasted 3 years being friends with Anna and a year and one summer with Ashley, but still, why are they ignoring me??