Hey Tilly! Lovely name, btw. I've always liked it! ^^
Anyway; I think that it sounds like a good idea to tattoo something that means something to you, instead of just doing something random. I believe that you wont tire of it if it has a meaning to you!

As to the pain; I have a friend who tattooed just on his wrist (from where his hand ends and about 7
cm (about 2,75inch) towards his elbow), and he said it hurt a lot. It was his first tattoo, and I'm not sure how much pain he can stand. But I've heard that the wrist is one of the most painful places to get a tattoo, however I might be wrong.
I hope that it works out, and that it's not too painful. Sorry if this wasn't of much help, but I don't have any tattoos myself

Cheers!