Day one of GuardianCon and I can see people aren't comfortable introducing themselves to others. The anxiety is flaring up, and it can be a little uncomfortable, even for an extrovert like me. But you will regret not introducing yourself to the person you are fangirling over, I promise you that. I had the opportunity to meet the drummer of Fall Out Boy outside of a Noodles & Co at one point, someone whom I very much admired. To this day it's still one of my biggest regrets.
My encouragement to you, is to go in for the introduction. At the end of the day, these folks are just people too. We all eat, sleep and poop. We all have feelings, and we all crave social interaction. Don't let worry stop you and worst of all, don't let your own anxiety get in the way of a potentially life-altering introduction. God bless!