Feel fine to laugh...

Angela • Twenties, engaged to the love of my life, yoga teacher, student, & student teacher 🕉❤️✌🏻☮
So my boyfriends little sister love to call me old. She's 14 and as of Tuesday I'm now 22. My niece who's 11 loves to call me old. As of now my nephews are the only ones getting Christmas gifts (just kidding).
My question is does anyone else feel old in only their early twenties? The only wrinkles on my face are laugh lines, but my hairs thinned a little, I get tired when working out a little faster... I'm a freaking yogini but put me on an elliptical and watch me cry. Am I the only one feeling this ridiculous? I'm going to see 3 doors down tomorrow and am trying on make up trends. It's not working out. 
If you read all that, or didn't here are my 3 main thoughts- does anyone feel old in their early 20s? Advice on how to emotionally realize this is ridiculous? And advice on what to wear/how to do my makeup for the concert?