I have two that I got when I was 16 and 19. I took three years between those because it took me that long before deciding on something I really wanted. Just recently (I am almost 34), I have been entertaining the idea of a third, but really don't know what I would get yet. I am thinking maybe I should wait until I am done having kids (I plan to have one more in a year or so) and then get something symbolic of motherhood.

ETA. To this day, I still love the tattoos I got and have zero regrets