Toxic??

Im in a toxic relationship. Ik it. And im scared to leave it. He took my virginity and im 13. He’s cheating on me, told me he was and always texts other females. We have been together for almost a month and he took my virginity on the second date. I didn’t mean for it to happen. I didn’t want it to happen. But it did. And now im stuck with that for the rest of my life. He took my virginity. So if i tried to get into another relationship i would eventually have to tell them im not a virgin and someone else has had sex with me. Im scared he might tell people. He doesn’t post me, only ft me when i post something he doesn’t like or I start “tripping”. I barely get a text. Im currently on delivered and he has posted on his snap story. Everytime he comes over he tries to do something sexual. But the few times he doesn’t and we just chill he knows exactly the words to say to me to make me stay. I had to lie to my mom and tell her my coochie has been feeling uncomfortable so she can make me a gynp appt. i just want to make sure i don’t have any std’s.i pray im not pregnant, the only circumstance would be from precum. I took a cheap pregnancy test and it said negative but ik they can be wrong and i got my period but i done research and you cab have your period early on in pregnancy so im praying for the best. He doesn’t understand how big of a deal that is.I feel so unhappy. Im just a fuck buddy. And i trusted him with my body. He was my first everything. I don’t want to leave. I want him to change so bad. I try my hardest everyday to act & look perfect for him. I try to be my best for him. And im still obviously not good enough. If i was good enough he wouldn’t want to cheat.