I just realized that there's no reason for me to feel insecure because when I'm older non of these stupid, insecure feelings will matter and that I'll just laugh at it all in the end....
Probably. Time and distance have a way of putting things in to perspective. Chances are, yeah, the things that bother you now are going to be the least of your problems later. Not worth a 2nd thought. You're one of the lucky few who realize that in the moment. :)