AIO when confronting my cousin?

Hey guys, me and my cousin get along pretty well.

He has a little bit of a temper and after a long time something happened again. We dont meet a lot as I am quite busy. We meet maybe once every 2 or 3 months, although we live opposite of each other. Me and my family are living above my grandparents and my cousins family opposite of us.

My grandpa has a car and sometimes I have to drive him somewhere or it has to get repaired. Most often my cousins mother (my aunt xd) drives with it though and he does too.

Nevertheless, a ticket arrived today, or a bill, whatever you wanna call it in which my grandpa was informed that he didnt pay his parking-ticket a month ago and now has to pay 120 dollars. Thing is, he rarely drives his car.

So now the question arrises, who drove the car that day (at that time)?

I immediatly talked to my father if I or he drove it or we drove it together. We went through photos and messages to confirm what we did that day. We saw that we were somewhere completely different, far away and we had proof. We looked thoroughly and doublechecked.

Later that day my cousin came up to my/my family's appartment and confronted me with the ticket/bill I just described and said maybe this is our responsibility. I looked at it and said "did you ask your mother?", a normal question I assume^^ And with a slight smirk he said "my mother/parents were away that day and I was too actually".

Alright. I then said "well, I talked to my father ..."

And then he immediatly interrupted me angrily and said "well this is your ticket" and immediatly left or wanted to close the door.

This was so unbelievably disrespectful. We are both grown adult and had pretty good moments in the last months. I felt very triggered because ... I mean... this was the most normal thing to just talk to each other and exchange information? No? I felt very disrespected.

I went after him and said "well I am going to lay the bill/ticket down to grandpa again" and added in a somewhat stronger and more urgent voice "do you wanna leave this house??".

I told him if everything is okay with him and how he imagined just coming into my house and just being stressy and pulling this off? He immediatly reacted with "what? I just came up to you and asked calmly"

That was enough, gaslighting me too after 10 seconds it happened. I dont understand... I mean... what do you think about my reaction? Was it too much? Should I just have staid calm and not react?