My advice, especially to somebody as young as you are....
Do NOT get a tattoo unless you KNOW you want it for at least a year. If you want that tattoo now, wait a year, if you STILL want it, go for it. Chances are, you'll change your mind within a year.
2nd piece of advice: make sure the artist is TALENTED. Crappy tattoos are some of the worst things to be stuck with...FOREVER.
I'm speaking from experience on both accounts. I have tattoos I got when I was your age that I wish I didn't get. I also have crappy tattoos that I wish I didn't get.