What should I do???????

Okay now I have a friend named Autumn (girl) and a ex friend named Veronica. Veronica asked me to buy her something at the bookfair i said no politely and then she said plz ill be ur bff i said " im not buying you anything". Then i told autumn id by her something if she'd skip music homework she did and my friend emiley came down and told her to go the teacher said so i bought 2 books for myself i didn't no what autumn wanted. And i came back and Autumn was just giving me dirty looks and i said r u my friend shes like god idk! and rolled her eyes it made me want to cry and shes been hanging out with my ex and talking and looking at me and when i looked mad veronica whispered to autumn something and they laughed and looked at me again and at the end of the day veronicas like oh yeah and autumn said and then autumns like dont tell her i will and autumn said to call her so i did about 10 times her sister answered and said shes not here so i called like 4 hours later and her mom answered and said " you know what your stalking my daughter you keep calling and your pissing me off where's your mother. i hung up she called back im like sorry shes like sorry oh yeah wheres your mother im like my parents arnt here shes like your home alone im like no my dads here and i gave the phone to my dad and my dad's pissed. i have to deal with this tomorrow whats autumns problem? what should i do? HELP! im 13 year old girl on my period also