How are you holding up rainbow?

As for your question. Nah, you didn’t cross any boundaries. That stuff was just lying there for people to see. Besides, her art is also displayed in public - and being on your way home, you might have come across it anyway. Not like you rummaged through her stuff... And if it were private, it shouldn’t be lying there in public in the first place.

It’s great that you told her (though you shouldn’t feel guilty or bad about it). Shows the closeness in your relationship with T. I don’t think she will be angry - she has no right to be, at any rate.