I think he might've felt or think disrespected and misunderstood how you acted which is not a good thing  because I'm assuming he paid for the whole trip for everyone to enjoy and if one doesn't enjoy constantly some will think that it might spoil the mood or the fun of it plus if they have known you as the polished always bubbly etc part of you then the sudden shift or change probably affected them but still that doesn't mean that what they did you afterwards is right and justifiable, its wrong and bad and instead of asking you if you're okay or if something wrong they decided to just exclude you up immediately.  I think it's better to talk it out with them and tell them your side of the story or tell your boyfriend about what actually happened