I dont feel comfortable around my bf:/?

okay so i was playing truth or dare with my sister , boyfriend , boyfriends brother(my sisters boyfriend) , and our bestfriend.Our parents were gone it was just us 5.We were all sitting in a circle. it was my sisters turn and of course she picked me and i picked dare and she dared me to kiss my boyfriend for 15 seconds , tounge and everything. So i went in for it. I liked it , it was better than my sisters dare.I dared her to give her boyfriend a bj for 2 minutes, and she was horny already so she went in for it. after two minutes they were exausted. So it was her turn to chose my boyfriend and he was dared to finger me but we had to go in my room.I wasnt weirded out just scared . so we went upstairs and i got ready after 2 mintutes we laid there for a minute and my sister walked in a threw a condemn on the dresser and i was confused at first then he told me he and my sister planned for us too have sex that night since she had lost her virginity to her bf two days ago(she wasnt afraid to do anythign now) Okay so there i am terified as ever and he gets up grabs the condemn and lays back down beside me and he says "do you want to do this" and i said yes but no . and he said yes or no? and i said idk so i got up n went downstairrs and he followed me and we sat back down with eerybody else and my sister smiles and says well what hapened and i said i didnt do it and she said why i said bc maybe if u wuldve told me i wuldve done it! We argued back and forth for about 3 minutes. and finally my boyfriend say Kam i need to talk to you can we go upstairs? so i went up there and sat down and he said i really wanna do this but its up to you. I said well i do to but it ust kinda suprised me bc i didnt know you wanted this and he said i have for a long time i just didnt know how to tell you.and i said are you ready and he said i guess so. so we undressed and we just played around too make me aroused. i was really wet. we decided not too use a condemn since im on birth control.We were ready to begin. We got in the position (missionary) we went to push in and it hurt , so he pulled out for a minute and went back in this time i told him to push through . and he did , it hurt sooo bad and he pulled out after he saw my reaction he pulled out , itold him to keep going so he went back in and his thrusts got deeper , he came after 5 minutes. i felt it when it shot out . I came about 10 minutes later. After came he ate me out and i screamed in delight . it felt really good. After about 3 hours of switching we got our clothes on ad when downstairs and everybody was sitten on the couch waiting for us and they said y'all were up there mighty long how did it go.and we explained then we sat down and finished watching the movie with them. When we all fell asleep . The next morning i woke up and me and my sister made breakfast for everybody. When i woke up my boyfriend to eat he went in too kiss me i tensed up . i couldnt do it. so i huggged him and we got our plates and came back and sat down .after we ate we went upstairs and laid down and he went for a kiss and i tensed up again! . I just dont feel confortable around him now!? I hate it bc i love when we kiss! why am i doing this? all of us were 12 .please help:/