I think i just got raped??? Help!!?

ok so i was at the park with my friends and then they all had to leave but me and this one guy stayed and i didn't know him that well but he was kinda my friend but i knew that he like m eso we were like talking and siting on the bench and the he kept sitting closer and i was like moving away and the he put his hand on my boob and i almost screamed but he said he had a gun and if i said or did anything he would shoot me so the he stuck his hand down my shirt and was touching my boobs and moaning. the he told me to go behind the bathroom where no one could see us and he told to to lay down so i did and he was like touching my boobs again then he took of my **** and i was in only my bra and he told me he was like really hard and i wanted to die. the he touched my boobs more then he moved down and started rubbing my p@@@y and then he kissed it and took of my pants and was rubbing me and the he took all all his clothes and said if i dint suck on his d$$k he would shoot me. So i wont say any details after but he raped me and i was like sobbing the entire time so what should i do. I fell soo sick and what if i get aids or hiv. or pergnet??? help what should i do????