Being left out of my group of best friends?

At my school, I have a group of best friends (5 people including me). However, over five months ago, my four best friends decided to do this dance/theatre performence for a school event. Theyve been going at it like crazy since then and today they performed it. i applauded them and supported them all the way. Right now, they are out for dinner including some stage crew helpers. I still can't help but feel left out though. I don't know what to do to feel better.