Fed up

Was waiting in line for self check out and probably had 5-6 items? I see one open up and just as I’m getting to it, a man from out of nowhere cuts me and I genuinely just thought he didn’t see the line so I tell him “hi I was next, the line is over there.” He has the nerve to tell me “yeah it’ll only take a minute.” He was talking on the phone at the same time too when he turned is back to me. What the fuck do I look like? Your mom? I literally took the scanner and got right up next to him (I don’t recommend and I now realize I shouldn’t have gotten so close) and told him “no you can go to the back. Why do I have to wait on you? We literally almost have the same amount of items.” I cursed him out. I don’t know why he frustrated me so much in this very moment. I’ve let people cut me before. He was shocked that his jaw was dropped and employees escorted him to another counter. I paid and walked out happy I stood up for myself but also why was I yelling about this lol.
Hope your day is better