I don't think it is sad or embarrassing to miss the most carefree time of your life.. I worked a concert for the jazz band I used to be a member of and watching them just be kids in between/after playing stirred something within me. It's a precious, unique time that nobody ever seems to appreciate until it's long gone. I have very fond memories of those years and haven't been able to hang out with friends as often and consistently as I did then. I didn't have the freedom of being an adult yet but the world wasn't nearly as big either, so it didn't feel limiting. Sometimes people put this down as "peaking in high school".. I think peaking is nonlinear and different aspects of your life can be at their best at different times.. There's another thought to be had here but I don't have the words to finish it right now lol.. maybe at a later time