McDonald's complaint

So I went through the drive through at McDonald's last night and what do you know, my little shit of a 15 year old brother was working and when I paid for my sundae, he literally threw the change at me (coins) and it landed under my passenger seat.
I plan on putting in a complaint with his manager but I was wondering if my complaint will be taken seriously? Family or not, I'm not putting up with that level of disrespect for absolutely no reason. Am I wrong for this?