Panic Attack on Fourth of July

Last fourth of july I was home alone at night without my dog. I am afraid of being alone at night but I’m not sure where this stems from. Anyways, i was afraid to leave my room and once i finally did i started to bake which is usually a comfort for me. all of a sudden i had the worst panic attack of my life i felt like someone was sitting on my chest and i started to hit my ribs with my fists trying to get myself to breathe. my parents came home and found me on the floor with wide eyes and a red face mouthing “i cant breathe”. my mom held my arms down and hugged me tight which made it worse. she tried to take me to the hospital and after about two hours of panicking i began to calm. the only thing that was happening was fireworks but i haven’t had a bad experience with them, now they trigger me. does anyone know why this happened????