The Survival

You are in school.You went to the bathroom. you start to hear weird noises from the halls of the school,Like someone would scream,and people running.You are feeling weird about this.You get to the entrance of the bathroom and you open the door,no one notices,you see blood on the floor and you instantly get scared and shocked.You see a figure in the hallway,You close the door and get back into the bathroom.You try to stay behind the door to block it.What will you do next ?