Friends mad because i forgot to call them

this is my first "is it normal" entry

well, this happened recently... just yesterday. i just slept over at one of my best friends houses, just me and her. the next day before i left she said, "call me. come to my house." she said that beacuse i was going to be at my house while my parents did chores around the house so, she said i could come over after i went home and showered and all that jazz. then my other friend came over without me knowing... just coming to my house, no notification at ALL. i didn't want to be rude and be like "you didnt even call me! i have plans! call me next time!!" but i didn't say anything at all. then we spent a little time at my house, just hangin and all. i didn't want her here. not because i didn't like her, but youn know, i had plans. i forgot to call my friend back. then my boyfriend texted me "im at the YMCA, come swim with me" i knew i wanted to go. i asked my friend if its alright and she said it was ok. we ended up going to the YMCA and swimming alltogether, including my friend. not the friend that i was supposed to call, but the one at my house. then when we were done, me and my friend went in the back to get our bikes, cuz we rode them there. my cell phone was in the pouch on the bike and i took it out and checked it. there were several text messages from my friend saying "YOU WERE SUPPOSED TO CALL ME AND INSTEAD TO GO SWIMMING WITH (my friend) BY URSELFS!!" and just then i became so scared!! we had a text fight and finally she and me relaxed. she told me to come to my other friends house to see her 2 new hamsters, me and my friend. when we got there, there were more of my friends there also. one of them came down the stairs, and glaired at me. i didn't know what the hell i did to her. then we went up to her room. there my friends talked normally with me, not like usually... but i was just gratful for that. when my mom called me and told me i had to come home with my friend, we said goodbyes. but my one friend only said goodbye to the friend who was with me. i see them again tommorow, and ive made sorry things and stuff for them and all. and i know they'll forgive me and all. this is not really a "is it normal" kinda thing, but it is a what should i do kinda thing. thank you.