Is the DM Always Right?

I recently got into a disagreement with my DM for a DND 5E game regarding a use of Prestidigitation.

The argument was that since it could create a Non-Magical Trinket, and Music Boxes are specifically listed in the Trinket section of the book, I should be able to make one, even if it is only temporary.

Her argument was that a music box did not fall under her definition of a trinket.

I’ve asked about the D&D 5e rules for that situation already, but now I’m asking whether the DM has the authority to change that rule in our game if she wants.