i did something i never thought possible

so yeah im new here and its like im just trying to figure things out after breaking up with my longterm partner. we were in an open relationship for a while but honestly i was always the one being faithful, you know? i mean dont get me wrong, there werent any hard rules but it felt kinda wrong or something. so last week at this club... man i went out and had this vodka soda punch and i met this girl, let's call her julie. she looked like a model, blonde hair blue eyes, all that shit. we were talking and drinking and stuff and before long i was feeling kinda wild. julie asked me if i wanted to go somewhere private with her. at first i thought about my old rules and hesitated but... hey i had just left the relationship and i figured why not? so we snuck out into this back room, a dark corner kinda thing. it was so intense, i could feel every single part of her as soon as our lips touched. she pushed me up against the wall, my skirt riding way up high, and i couldnt believe how wet i already was for her. julie's hands were everywhere, grabbing at my breasts and slipping under my top to stroke my nipples until they were hard little peaks. i spread my legs wider so she could feel how much i wanted this. then she pulled down my panties with one quick motion and plunged two fingers deep inside me right then and there on that dirty wall. i was moaning so loud but nobody around us seemed to care, just lost in the moment as her digits filled me up over and over again until i was soaking wet, trembling for more. when we finally got it together enough to find a bed somewhere, its like things escalated even faster. i laid back with my legs spread wide open invitingly and julie wasted no time thrusting into me hard with the strap-on she had brought along. fuck i couldnt get over how big it felt stretching me so thoroughly, her hands pinning my thighs down as she pounded in deep again and again. we were both screaming out each others names, losing ourselves in pure animal passion for hours before we collapsed back into reality. but the guilt? oh man, the next day i was a wreck. what if this happens again? am i still me at all anymore? i just... dont know where to go from here.