I think it sounds 'normal' (whatever that is!) and not attention-seeking at all. Just like you want to share this new thing with your T. To me it definitely doesn't sound like you're getting the tat for attention, or making a big kerfuffle of wanting to show it to her.

Sharing parts of yourself is essential for all relationships, or they don't work. I'm guessing it's going to be placed kind of on your breast bone, above your breast as such, so it's going to be mostly visible if you have a V-neck tshirt on? So no undressing involved.