Is this girl like stalking me?

so, i went to the movies to see a movie like about a month ago. and i went with three other dudes and two girls, so i went to get popcorn and this chick comes up to me and is like hey. im like alright she cute i said it back. in the movies she sat right behind me, we left outside and she was walking behind us. one my girl friends told her to go screw off. the girl left but wen i was walking home(i live close) she came down my street and started talkin to me. soo since that day shes been coming around throwing little pebbles at my window and yesterday i was with the girl i liked alot(different girl) and this chick throws pebbles and tells the girl i like to get out so she can beat her ***. but i obviously didnt so this chick went pycho and tried opening my door. my mom calld the police but the chick left. and today she like sitting in my front yard right now and i dont wanna be rude and call the cops but is she stalking me?