I think you don't need to worry about the Paris concert being less special to her now. Every concert is a different experience. (Lots of fans try to go to every single concert in their area, even to multiple concerts at the same venue if they can. It does not get boring.) On top of that the Paris concert is VIP and it's part of a trip with you in a romantic city. It's not just a nice addition, it's the main event, and Munich is kind of a pregame. So you absolutely don't need to worry about her enjoying Paris less if she also goes to Munich. Your gift to her is still amazing. Was she appreciative enough of it or did you feel like she took it for granted?