Am I being a bit petty over a Christmas photo?

Not sure if I'm being petty over taking a Christmas photo or not and wanted people's opinions...

I've travelled over with my partner to spend Christmas with her family for a few weeks. I got here and it's a few days till Christmas now. We took a drive, my girlfriend, her sister and brother to a Christmas market took 4 hours to drive.

We haven't really taken any couple pictures together for Christmas or in a short while. We went to a place with a lot of lights, displays, ferris wheel etc. and thought it would be nice to take some pictures.

My girlfriend ended up half way as I said about taking a picture together saying come here quick take a picture of me, my sister and my brother. So I did, after that she just dismissed and ignored about us taking a picture together. When I asked her about it she said its fine, we can just take a picture another time and told me to stop being upset.

I mean new place, once a year Christmas market we won't go back to... she was all up for getting a picture with her siblings but not with me. It's mostly pictures of the market and pictures of her and her siblings... its almost like I'm not even there. I was kind of upset on the 4 hour drive back.

Am I reasonable to be upset? Just wanted a nice couple photo in a place that we won't go to again
Am I being a bit petty over a Christmas photo?
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