3 Everyday Things that Make Me Feel Grown-up

Most days I still feel like a child. Its hard to believe that I in my fourth year of University. Sometimes though I get this fleeting feeling like "wow" I am actually grown up and at the same time I feel like I am just playing dress-up.  This feeling comes at random times, usually when I am doing everyday things. Things that I do on a regular (or semi-regular basis) but every once and a while it hits me that I am growing up and becoming an adult. They are:  1. Answering Emails. 

The more formal the email the older I feel. This also true to emails that are about scheduling things or that have multiple exchanges.
2. Wearing Heels. 

I feel SO tall and SO old. You could also add in when I am dressed business casual. 
3. Voluntarily Eating a Salad. 

No one is forcing me. Yet, once again I have picked a salad off the menu. SO grown up!
What makes you feel grown up?