Should I have stayed

Hi, I’m 14 M and was pretty bummed out today after a fourth of July event. what happened was me and my family were at a clubhouse for the fourth and there was a lot of free food and stuff. My Great Aunt saw some of her friends so we ate with them. the plan originally was to eat, play games outside and we were going to do a dunk tank. anyways, after we finished eating my great uncle says okay, who wants to go back to the house with me. and my mom and my second cousin say that they want to go back. At this point i was worrying because i thought I would have to go with them, I was also under the impression that we would all stay there until the end of the event. But my mom says do you want to come with us or stay here with your aunt and her friend and at this point I'm thinking it over because its either stay with 5 old people, four them being strangers (we’re in a 55+ community, forgot to mention that) and have a lot of fun but be mildly uncomfortable or just go home and be comfortable but have fomo and be sad. So i chose to leave because im socially awkward with strangers and didnt want to be uncomfortable but now Im sad because i still really wanted to go. I want to tell my mom how i feel but i don't want to come off as a brat and i feel like im just sick of always biting my tongue. anyways I posted this to express how i feel and hopefully get some advice. Happy Fourth, peace out