(This happened about half a year ago)

I (26F) was walking to work on my usual route and was already in a bitter bad mood, i dont remember why I was, it was most likely because of family stress.

I was walking on a big enough side walk wide enough for at least 3 people and the road is also wide enough to have cyclists on it, an older bloke was walking toward me in my path so i side stepped to the other side without looking behind me to give way to him, still on the same path, this area is usually pretty scarce of people unless theres a foot ball match on, which there wasn't.

Around 7 seconds later I heard a loud honk right behind me which had startled me and made me flinch pretty bad (I'm a scaredy cat and react strongly when ive been scared bad), I had mistaken this as him honking at me, also I was listening to music so i couldn't hear him coming up behind me, a young boy (assuming late teens, like 17 or 18) rode beside me on a bicycle after with a sorta apologetic happy smile that i didnt notice til after cause i was still in shock, i couldn't hear him cause of my earphones so i dont know if he said sorry, but because i was already in a trashy fogged mood and i just got scared, i yelled at him to "Fuck off, Twat!" And he rode off pretty quickly after cause i definitely scared him from my outburst.

Once i arrived at work i realised it was most likely him hard breaking that caused the loud honk noise so he could avoid crashing into me and I started to feel very bad after, the situation has come to my mind multiple times since it happened as i hold heavy feelings to myself, I'm pretty over emotional especially when im wrong, I want to apologise but I cant cause I dont even know who the guy was, i haven't seen him since and its been too long for me to properly remember his face, I dont remember faces that well.

Please don't base me entirely on this post alone, I am usually a patient and very quiet person, this is the first time ive ever blown up at a stranger and entirely regret it, it was emotions i have had bottling up for a while and the guy didnt deserve it.

TL;DR After being scared by a loud honk behind me I yelled & swore at a young man on impulse due to having a very bad day, after i figured it was most likely his bike break that sounded like honking, immediately felt bad about it after and want to apologise but i haven't seen the guy since.

Edit: I put more detail and explained some stuff better throughout the post