AITA because i don´t wanna be on photos at a wedding?

I (14m) have to go to my cousin’s wedding with my parents this Saturday. That already sucks-I hate weddings, I can’t stand formal clothes, and I absolutely hate shirts! And now my parents borrowed a suit from my cousin(from the other side of the family)… it’s one of those suits with a vest, a white shirt, and a bow tie. I knew I wouldn’t be able to get out of dressing up somehow, but I at least wanted a cool outfit like a black suit with a gray shirt or something. Definitely not a white shirt and absolutely no stupid bow tie. But my parents are saying that since I hate formal clothes anyway and won’t wear them again before I outgrow them, they don’t want to waste money. We had a fight about it, but no chance, I have to wear the full suit. I teased my cousin back then when he had to wear it. He hates formal clothes like me, and I made fun of him, said he looked like a choirboy in that outfit and that I would never let my parents force me to wear something like that, especially not a stupid bow tie. Now he’s already super annoying because my parents borrowed his suit for me. I told him I’d only wear it without the bow tie and without the vest. But I know he’s gonna stalk my family’s social media on Saturday, and if he sees a picture of me, I’m done. He’ll never let me live it down. He´s going to roast me for the next 10 years. My parents don’t know that and I can’t tell them, they are only getting annoyed with me.

I told my parents that I just don’t want to be in any photos at the wedding, but they say that would be rude and that I have to be in the photos. But why, I should be able to decide whether I want to be on photos or not?