I didn't want to share my camp-area at a festival with my girlfriend, but I later took in some random guys even though she asked first
Why did you turn her down?
I thought it was better to be alone, but I wanted to help these guys out.
It is nice to help others, but if your girlfriend asked first you should have given the space to her. You can apologize to make this right.
I now feel weird because gf asked for it first, but I was being nice by letting some random guy in. He also asked nicely with eye contact.
It was good of you to be generous to those who needed a place to stay, but the fact is that your girlfriend asked you first, and she deserved to be able to stay in your camp area. I hope you apologize to make this right.