How to look older ?

I am 25 and I am very petite. Everyone always says I look like I’m 15. And I hate it sometimes.

I know it’s nice to look young but I feel like people don’t take my seriously sometimes. I recently got a new job , and the older women all make comments about how I’m not a “woman” and I look like a “little girl” and it’s embarrassing.

I just got my first tattoo on my back. Do you think getting tattoos on my arms would make me look older ?

I also try to wear a lot of makeup and wear “mature” clothing.